Quantum Connections in Sweden-10 Summer School

12 Jun 2022, 07:00 → 25 Jun 2022, 12:00 Europe/Stockholm

Fåhraeus salen (Högberga Gård)

Frank Wilczek (Stockholm University)

Venue

Högberga Gård, Lidingö, Sweden

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Scope

The Quantum Connections 2022 is part of the Quantum Connections series of scientific events, a summer school that is organized for graduate students and postdocs in all aspects of quantum frontiers.

Quantum Connections events are organized jointly by the Department of Physics and Nordita (hosted by Stockholm University, KTH-Royal Institute of Technology, and Uppsala University), together with TD Lee Institute and Wilczek Quantum Center at Shanghai Jiao Tong University.

Curriculum: Short courses from Quantum Matter, Quantum Information, and Quantum Sensing. From theory to computations and experimental results.

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Invited Lecturers

Name
Pavel Belov
Emil Bergholtz
Michael Berry
Annica Black-Schaffer
Paola Cappellaro
Yuao Chen
Steve Girvin
Martin Greiter
Michael Manfra
Charles Marcus
John Martinis
Alexander Millar
Sid Morampudi
Jianwei Pan
Igor Pikovski
Frank Wilczek
Nicole Yungern Halpern
Martin Zwierlein

 

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Poster

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Accommodation

For the "non-local" participants who don't live in the Stockholm area, we have provided accommodation at the summer school's venue and will send the information to those participants individually.

Please be aware that unfortunately, scammers sometimes approach participants claiming to be able to provide accommodation and asking for credit card details. Please do not give this information to them. For invited speakers and also successful applicants, organazers will always be in touch via email regarding accommodation. If you are in any doubt about the legitimacy of an approach, please get in contact with the organizers. quantum.connections@fysik.su.se

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Application

The intended audience is Ph.D. students and junior researchers in quantum phenomena and condensed matter physics.

You apply to the Quantum Connections School in two steps:

1. Fill in the APPLICATION FORM in the menu to the left
2. Ask your supervisor or another reference person to send a recommendation letter via e-mail to:quantum.connections@fysik.su.se. The subject line should contain: "QC2022" and "name of the applicant".

Both steps must be completed by March 30, 2022.

You will be informed by the organizers shortly after the application deadline whether your application has been approved or not. Due to space restrictions, the total number of participants is strictly limited.

There is no registration fee. We will cover the local expenses (housing, meals, airport transfer) for non local participants during the school. Participants cover their own travel expenses to Stockholm.

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The Organizing Committee

• Frank Wilczek (Chair)	Stockholm University, Stockholm
• Egor Babaev	KTH-Royal Institute of Technology, Stockholm
• Emil Bergholtz	Stockholm University, Stockholm
• Hans Hansson	Stockholm University, Stockholm
• Wei Ku	Shanghai Jiaotong University, Shanghai
• Antti Niemi (Scientific coordinator)	Stockholm University, Stockholm
• Pouya Peighami(Event coordinator)	Stockholm University, Stockholm
• Alfred Shapere	University of Kentucky, Lexington
• Biao Wu	Peking University, Beijing
• Elizabeth Yang	Stockholm University/Nordita, Stockholm

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COVID-19 Restrictions

We will keep the participants updated about any changes in the restrictions and if they will affect the event.

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Sponsored By

 

 

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Contact

quantum.connections@fysik.su.se

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Sunday 12 June

07:00 → 19:00 Check-in (for participants from abroad and lecturers)

Monday 13 June

08:00 → 09:15 Registration

09:15 → 09:30 Opening Session and information from organizers

09:30 → 10:30 New physics with superconductor-semiconductor hybrids

In these lectures, I will discuss the consequences of a recent breakthrough in material science, the growth of heterostructures containing superconductors and semiconductors. This includes studies of basic condensed matter physics, such as the superconductor-insulator transition and the so-called anomalous metal phase, to Majorana zero modes and gatemon qubits. In keeping with the theme of the workshop, I will emphasize resent results and opportunities in creating “designer networks” of Josephson junctions.

Speaker: Prof. Charles Marcus (Niels Bohr Institute, University of Copenhagen)

New physics with superconductor- semiconductor hybrids

10:30 → 10:45 Coffee Break

10:45 → 11:45 New physics with superconductor-semiconductor hybrids

In these lectures, I will discuss the consequences of a recent breakthrough in material science, the growth of heterostructures containing superconductors and semiconductors. This includes studies of basic condensed matter physics, such as the superconductor-insulator transition and the so-called anomalous metal phase, to Majorana zero modes and gatemon qubits. In keeping with the theme of the workshop, I will emphasize resent results and opportunities in creating “designer networks” of Josephson junctions.

Speaker: Prof. Charles Marcus (Niels Bohr Institute, University of Copenhagen)

11:45 → 13:00 Lunch Break

13:00 → 13:50 Superconducting Qubits

I will describe the basic physics of superconducting qubits, from a practical and intuitive point of view describing them as non-linear oscillators. I will also review the theory of the surface code, which is a good way to understand how fault-tolerant error correction works. All of this is put together in a review of the quantum supremacy experiment, where high-fidelity qubit operations are possible in a scalable system.

Speaker: Prof. Martinis John (University of California, Santa Barbara)

Quantum Computation & Quantum Supremacy

13:50 → 14:10 Break

14:10 → 15:00 Superconducting Qubits

I will describe the basic physics of superconducting qubits, from a practical and intuitive point of view describing them as non-linear oscillators. I will also review the theory of the surface code, which is a good way to understand how fault-tolerant error correction works. All of this is put together in a review of the quantum supremacy experiment, where high-fidelity qubit operations are possible in a scalable system.

Speaker: Prof. John Martinis (University of California, Santa Barbara)

Superconducting Qubits

15:00 → 15:30 Coffee Break

15:30 → 16:20 BEC-BCS Crossover and the Unitary Fermi Gas

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Speaker: Prof. Zwierlein Martin (Massachusetts Institute of Technology)

Strongly Interacting Fermi gases

16:20 → 16:40 Break

16:40 → 17:30 Realization of the Fermi-Hubbard Model with Quantum Gases

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Speaker: Prof. Zwierlein Martin (Massachusetts Institute of Technology)

17:30 → 17:45 Break

17:45 → 18:30 Q&A: with Marcus, Martinis, Zwierlein.

Question and answer session with the lecturers.

18:40 → 20:40 Welcome Drinks followed by Dinner

Tuesday 14 June

09:30 → 10:30 New physics with superconductor-semiconductor hybrids

In these lectures, I will discuss the consequences of a recent breakthrough in material science, the growth of heterostructures containing superconductors and semiconductors. This includes studies of basic condensed matter physics, such as the superconductor-insulator transition and the so-called anomalous metal phase, to Majorana zero modes and gatemon qubits. In keeping with the theme of the workshop, I will emphasize resent results and opportunities in creating “designer networks” of Josephson junctions.

Speaker: Prof. Charles Marcus (University of Copenhagen)

10:30 → 10:45 Coffee Break

10:45 → 11:45 New physics with superconductor-semiconductor hybrids

In these lectures, I will discuss the consequences of a recent breakthrough in material science, the growth of heterostructures containing superconductors and semiconductors. This includes studies of basic condensed matter physics, such as the superconductor-insulator transition and the so-called anomalous metal phase, to Majorana zero modes and gatemon qubits. In keeping with the theme of the workshop, I will emphasize resent results and opportunities in creating “designer networks” of Josephson junctions.

Speaker: Prof. Charles Marcus (University of Copenhagen)

11:45 → 13:00 Lunch Break

13:00 → 13:50 Superconducting Qubits

I will describe the basic physics of superconducting qubits, from a practical and intuitive point of view describing them as non-linear oscillators. I will also review the theory of the surface code, which is a good way to understand how fault-tolerant error correction works. All of this is put together in a review of the quantum supremacy experiment, where high-fidelity qubit operations are possible in a scalable system.

Speaker: Prof. John Martinis (University of California, Santa Barbara)

The Challenge: Qubit Errors

13:50 → 14:10 Break

14:10 → 15:00 Superconducting Qubits

I will describe the basic physics of superconducting qubits, from a practical and intuitive point of view describing them as non-linear oscillators. I will also review the theory of the surface code, which is a good way to understand how fault-tolerant error correction works. All of this is put together in a review of the quantum supremacy experiment, where high-fidelity qubit operations are possible in a scalable system.

Speaker: Prof. John Martinis (University of California, Santa Barbara)

15:00 → 15:30 Coffee Break

15:30 → 16:20 Fractionalization of charge and statistics in two dimensions

A basic tenet of quantum mechanics is that all elementary particles are either bosons or fermions. Ensembles of bosons and fermions may act differently due to differences in their underlying statistical properties. For example, much of the electronic structure of ordinary solids may be explained by symmetry and noting electrons are fermions and obey the Pauli exclusion principle – fermions cannot exist in the same quantum state simultaneously. On the other hand, integral spin atoms and photons are bosons and are not constrained by the Pauli principle. Bose-Einstein condensation and superfluidity are some of the most spectacular properties of bosons. Starting in the early 1980’s it was theoretically conjectured that excitations that are neither bosons nor fermions may exist under special conditions in two dimensional systems. These unusual excitations were dubbed “anyons” by Frank Wilczek. Anyons may have fractional charge and fractional statistics, however directly probing these properties presents experimental challenges. My lectures will focus on experiments that demonstrate fractional statistics have observable consequences for the two-dimensional electron gas in the fractional quantum Hall regime. While theory indicated the necessity of anyons from the earliest days of the fractional quantum Hall effect, experimental verification has required many advances in materials, experimental probes, and understanding of the operation of electronic Fabry-Perot interferometers in the quantum Hall regime in real devices. I hope to describe how these challenges were met through the work of many groups over the last few decades and outline the physics that remains to be explored in future generations of experiments.

Speaker: Prof. Michael Manfra (Purdue University)

Fractionalization of Charge And Statistics in Two Dimensions

16:20 → 16:40 Break

16:40 → 17:30 Fractionalization of charge and statistics in two dimensions

A basic tenet of quantum mechanics is that all elementary particles are either bosons or fermions. Ensembles of bosons and fermions may act differently due to differences in their underlying statistical properties. For example, much of the electronic structure of ordinary solids may be explained by symmetry and noting electrons are fermions and obey the Pauli exclusion principle – fermions cannot exist in the same quantum state simultaneously. On the other hand, integral spin atoms and photons are bosons and are not constrained by the Pauli principle. Bose-Einstein condensation and superfluidity are some of the most spectacular properties of bosons. Starting in the early 1980’s it was theoretically conjectured that excitations that are neither bosons nor fermions may exist under special conditions in two dimensional systems. These unusual excitations were dubbed “anyons” by Frank Wilczek. Anyons may have fractional charge and fractional statistics, however directly probing these properties presents experimental challenges. My lectures will focus on experiments that demonstrate fractional statistics have observable consequences for the two-dimensional electron gas in the fractional quantum Hall regime. While theory indicated the necessity of anyons from the earliest days of the fractional quantum Hall effect, experimental verification has required many advances in materials, experimental probes, and understanding of the operation of electronic Fabry-Perot interferometers in the quantum Hall regime in real devices. I hope to describe how these challenges were met through the work of many groups over the last few decades and outline the physics that remains to be explored in future generations of experiments.

Speaker: Prof. Michael Manfra (Purdue University)

17:30 → 17:45 Break

17:45 → 18:30 Q&A: with Marcus, Martinis, Manfra.

Question and answer session with the lecturers.

19:00 → 20:00 Dinner

Wednesday 15 June

09:30 → 10:30 Exploring the gravity-quantum interface at low energies

The search for a quantum theory of gravity is one of the main challenges of modern physics. One major challenge is the lack of observable signatures that can guide theoretical developments. But in recent years, the interplay between quantum physics and general relativity at low energies has emerged as a promising new cross-disciplinary research field. The rapid progress in experimental control of quantum systems at novel scales, and a fresh quantum information perspective, have opened new opportunities for table-top tests to shine some light on this mostly unexplored regime of physics. In this lecture series, I will discuss some examples of this new field, from tests of Post-Newtonian quantum dynamics to quantum gravity phenomenology.

Speaker: Prof. Igor Pikovski (Stockholm University)

10:30 → 10:45 Coffee Break

10:45 → 11:45 Exploring the gravity-quantum interface at low energies

The search for a quantum theory of gravity is one of the main challenges of modern physics. One major challenge is the lack of observable signatures that can guide theoretical developments. But in recent years, the interplay between quantum physics and general relativity at low energies has emerged as a promising new cross-disciplinary research field. The rapid progress in experimental control of quantum systems at novel scales, and a fresh quantum information perspective, have opened new opportunities for table-top tests to shine some light on this mostly unexplored regime of physics. In this lecture series, I will discuss some examples of this new field, from tests of Post-Newtonian quantum dynamics to quantum gravity phenomenology.

Speaker: Prof. Igor Pikovski (Stockholm University)

11:45 → 13:00 Lunch Break

13:00 → 13:50 Fractional statistics

In two and one spatial dimensions, we have the possibility of anyon statistics, that is, quantum statistics of identical particles which interpolates between the canonical choices of fermions and bosons. The mathematical reason is that in a path integral formulation, the group describing interchanges is not the permutation, but the braid group, which, in two dimensions, has a continuum of one-dimensional representation labeled by a U(1) phase parameter θ.
Physically, this statistical parameter describes the phase acquired by the wave function as we interchange two anyons by winding them counterclockwise around each other. This phase leads to a fractional shift in the allowed values for the relative angular momenta.
Anyons can be realized by composites consisting of electric charge and infinitesimally thin magnetic flux tubes. Restrictions for fractional statistics on closed surfaces can be traced back to
Dirac’s monopole condition. In field theory, statistical transmutations, and in particular anyon statistics, can be implemented very naturally by a Chern-Simons term in a fictitious gauge field, which attaches both charge and flux tubes to the particles.
The quasi particle excitations of fractionally quantized Hall states obey anyon statistics. In one dimension, the crossings of anyons on a ring are always uni-directional, such that a fractional phase θ acquired upon interchange gives rise to fractional shifts in the relative momenta between the anyons. In non-Abelian generalizations, anyons span an internal space of (degenerate) states and transform under higher dimensional representations of the braid group as we wind them around each other. Since the internal state vector is insensitive to local perturbations, non-Abelian anyons may prove instrumental in the construction of fault-tolerant quantum computers.

Speaker: Prof. Martin Greiter (Julius-Maximilians-Universität)

Lectures Fractional Statistics

13:50 → 14:10 Break

14:10 → 15:00 Fractional statistics

In two and one spatial dimensions, we have the possibility of anyon statistics, that is, quantum statistics of identical particles which interpolates between the canonical choices of fermions and bosons. The mathematical reason is that in a path integral formulation, the group describing interchanges is not the permutation, but the braid group, which, in two dimensions, has a continuum of one-dimensional representation labeled by a U(1) phase parameter θ.
Physically, this statistical parameter describes the phase acquired by the wave function as we interchange two anyons by winding them counterclockwise around each other. This phase leads to a fractional shift in the allowed values for the relative angular momenta.
Anyons can be realized by composites consisting of electric charge and infinitesimally thin magnetic flux tubes. Restrictions for fractional statistics on closed surfaces can be traced back to
Dirac’s monopole condition. In field theory, statistical transmutations, and in particular anyon statistics, can be implemented very naturally by a Chern-Simons term in a fictitious gauge field, which attaches both charge and flux tubes to the particles.
The quasi particle excitations of fractionally quantized Hall states obey anyon statistics. In one dimension, the crossings of anyons on a ring are always uni-directional, such that a fractional phase θ acquired upon interchange gives rise to fractional shifts in the relative momenta between the anyons. In non-Abelian generalizations, anyons span an internal space of (degenerate) states and transform under higher dimensional representations of the braid group as we wind them around each other. Since the internal state vector is insensitive to local perturbations, non-Abelian anyons may prove instrumental in the construction of fault-tolerant quantum computers.

Speaker: Prof. Martin Greiter (Julius-Maximilians-Universität)

15:00 → 15:30 Coffee Break

15:30 → 16:20 Quantum thermodynamics

Thermodynamics has shed light on engines, efficiency, and time’s arrow since the Industrial Revolution. But the steam engines that powered the Industrial Revolution were large and classical. Much of today’s technology and experiments are small-scale, quantum, far from equilibrium, and processing information.
Nineteenth-century thermodynamics needs re-envisioning for the 21st century.
Guidance has come from the mathematical toolkit of quantum information theory.
Applying quantum information theory to thermodynamics sheds light on fundamental questions (e.g., how does entanglement spread during quantum thermalization? How can we distinguish quantum heat from quantum work?) and practicalities (e.g., quantum engines and the thermodynamic value of coherences).
I will overview how quantum information theory is being used to revolutionize thermodynamics.

Recommended reading: Yunger Halpern, Quantum Steampunk: The Physics of
Yesterday’s Tomorrow, Johns Hopkins U. Press (2022).

Speaker: Prof. Nicole Yunger Halpern (University of Maryland - College Park)

Quantum Thermodynamics

16:20 → 16:40 Break

16:40 → 17:30 Quantum thermodynamics

Thermodynamics has shed light on engines, efficiency, and time’s arrow since the Industrial Revolution. But the steam engines that powered the Industrial Revolution were large and classical. Much of today’s technology and experiments are small-scale, quantum, far from equilibrium, and processing information.
Nineteenth-century thermodynamics needs re-envisioning for the 21st century.
Guidance has come from the mathematical toolkit of quantum information theory.
Applying quantum information theory to thermodynamics sheds light on fundamental questions (e.g., how does entanglement spread during quantum thermalization? How can we distinguish quantum heat from quantum work?) and practicalities (e.g., quantum engines and the thermodynamic value of coherences).
I will overview how quantum information theory is being used to revolutionize thermodynamics.

Recommended reading: Yunger Halpern, Quantum Steampunk: The Physics of
Yesterday’s Tomorrow, Johns Hopkins U. Press (2022).

Speaker: Prof. Nicole Yunger Halpern (University of Maryland - College Park)

17:30 → 17:45 Break

17:45 → 18:15 Quantum-optical topological states in arrays of qubits

Speaker: Dr Maxim Gorlach

Photonic topological phases in superconducting circuits

18:15 → 19:00 Q&A: with Greiter, Yunger-Halpern, Gorlach

Question and answer session with the lecturers.

19:00 → 20:00 Dinner

Thursday 16 June

09:30 → 10:30 Quantum Simulations and Quantum Error Correction with Bosonic Modes

It is well-known that fermions are difficult to simulate with qubits because of their odd symmetry under
exchange. It is less widely appreciated that bosons, despite their even symmetry under exchange, are
also difficult to simulate with qubits. I will discuss how quantum hardware containing bosonic modes
(microwave resonators) offers great hardware efficiency for simulation of many-body and lattice gauge
models containing bosons. Time permitting, I will also discuss recent experimental success in quantum
error correction beyond the break-even point using the GKP bosonic code.

Speaker: Prof. Steve Girvin (Yale University)

Introduktion to Circuit

10:30 → 10:45 Break

10:45 → 11:45 Quantum Simulations and Quantum Error Correction with Bosonic Modes

It is well-known that fermions are difficult to simulate with qubits because of their odd symmetry under
exchange. It is less widely appreciated that bosons, despite their even symmetry under exchange, are
also difficult to simulate with qubits. I will discuss how quantum hardware containing bosonic modes
(microwave resonators) offers great hardware efficiency for simulation of many-body and lattice gauge
models containing bosons. Time permitting, I will also discuss recent experimental success in quantum
error correction beyond the break-even point using the GKP bosonic code.

Speaker: Prof. Steve Girvin (Yale University)

Programmable Quantum Simulators for Condensed Matter and Lattice Gauge Models

11:45 → 13:00 Lunch Break

13:00 → 13:50 Fractionalization of charge and statistics in two dimensions

A basic tenet of quantum mechanics is that all elementary particles are either bosons or fermions. Ensembles of bosons and fermions may act differently due to differences in their underlying statistical properties. For example, much of the electronic structure of ordinary solids may be explained by symmetry and noting electrons are fermions and obey the Pauli exclusion principle – fermions cannot exist in the same quantum state simultaneously. On the other hand, integral spin atoms and photons are bosons and are not constrained by the Pauli principle. Bose-Einstein condensation and superfluidity are some of the most spectacular properties of bosons. Starting in the early 1980’s it was theoretically conjectured that excitations that are neither bosons nor fermions may exist under special conditions in two dimensional systems. These unusual excitations were dubbed “anyons” by Frank Wilczek. Anyons may have fractional charge and fractional statistics, however directly probing these properties presents experimental challenges. My lectures will focus on experiments that demonstrate fractional statistics have observable consequences for the two-dimensional electron gas in the fractional quantum Hall regime. While theory indicated the necessity of anyons from the earliest days of the fractional quantum Hall effect, experimental verification has required many advances in materials, experimental probes, and understanding of the operation of electronic Fabry-Perot interferometers in the quantum Hall regime in real devices. I hope to describe how these challenges were met through the work of many groups over the last few decades and outline the physics that remains to be explored in future generations of experiments.

Speaker: Prof. Michael Manfra (Purdue University)

13:50 → 14:10 Break

14:10 → 15:00 Fractionalization of charge and statistics in two dimensions

A basic tenet of quantum mechanics is that all elementary particles are either bosons or fermions. Ensembles of bosons and fermions may act differently due to differences in their underlying statistical properties. For example, much of the electronic structure of ordinary solids may be explained by symmetry and noting electrons are fermions and obey the Pauli exclusion principle – fermions cannot exist in the same quantum state simultaneously. On the other hand, integral spin atoms and photons are bosons and are not constrained by the Pauli principle. Bose-Einstein condensation and superfluidity are some of the most spectacular properties of bosons. Starting in the early 1980’s it was theoretically conjectured that excitations that are neither bosons nor fermions may exist under special conditions in two dimensional systems. These unusual excitations were dubbed “anyons” by Frank Wilczek. Anyons may have fractional charge and fractional statistics, however directly probing these properties presents experimental challenges. My lectures will focus on experiments that demonstrate fractional statistics have observable consequences for the two-dimensional electron gas in the fractional quantum Hall regime. While theory indicated the necessity of anyons from the earliest days of the fractional quantum Hall effect, experimental verification has required many advances in materials, experimental probes, and understanding of the operation of electronic Fabry-Perot interferometers in the quantum Hall regime in real devices. I hope to describe how these challenges were met through the work of many groups over the last few decades and outline the physics that remains to be explored in future generations of experiments.

Speaker: Prof. Michael Manfra (Purdue University)

15:00 → 15:30 Coffee Break

15:30 → 16:20 Topological superconductivity

Topological states of matter have emerged in the last decade as one of the absolute most vibrant areas of condensed matter physics. These range from topological insulators and Weyl semimetals but also an abundance of different topological states in superconductors. The defining property for all these phases of matter is a global non-trivial topology of their electronic structure. This is fundamentally different from the traditional Landau paradigm traditionally used to classify matter, where local order parameters appearing due to spontaneous symmetry breaking play the key role. Topological superconductors are particularly interesting as they automatically join these two fundamentally different views of matter having both a global topological order and a local superconducting order parameter. Combining this with the distinctive particle-hole mixing in superconductors gives rise to emergent Majorana fermion states, that can be viewed as half electron quasiparticles offering unique possibilities to realize robust quantum computation.

In these lectures I will cover the basic theory of topological superconductivity. Starting from an elementary understanding of conventional BCS superconductivity and topological insulators, I will discuss several different topological superconducting states, as well as focusing on how and why Majorana fermions appear as topological protected edge states.

Speaker: Prof. Annica Black-Schaffer (Uppsala University)

Topological Superconductivity

16:20 → 16:40 Break

16:40 → 17:30 Topological superconductivity

Topological states of matter have emerged in the last decade as one of the absolute most vibrant areas of condensed matter physics. These range from topological insulators and Weyl semimetals but also an abundance of different topological states in superconductors. The defining property for all these phases of matter is a global non-trivial topology of their electronic structure. This is fundamentally different from the traditional Landau paradigm traditionally used to classify matter, where local order parameters appearing due to spontaneous symmetry breaking play the key role. Topological superconductors are particularly interesting as they automatically join these two fundamentally different views of matter having both a global topological order and a local superconducting order parameter. Combining this with the distinctive particle-hole mixing in superconductors gives rise to emergent Majorana fermion states, that can be viewed as half electron quasiparticles offering unique possibilities to realize robust quantum computation.

In these lectures I will cover the basic theory of topological superconductivity. Starting from an elementary understanding of conventional BCS superconductivity and topological insulators, I will discuss several different topological superconducting states, as well as focusing on how and why Majorana fermions appear as topological protected edge states.

Speaker: Prof. Annica Black-Schaffer (Uppsala University)

17:30 → 17:45 Break

17:45 → 18:30 Q&A: with Girvin, Manfra, Black-Shaffer

Question and answer session with the lecturers.

19:00 → 20:00 Conference Dinner

Friday 17 June

09:30 → 10:30 Topological superconductors and Majorana fermions Or Odd-frequency superconductivity

Speaker: Prof. Annica Black-Schaffer (Uppsala University)

10:30 → 10:45 Coffee Break

10:45 → 11:45 Topological superconductors and Majorana fermions Or Odd-frequency superconductivity

Speaker: Prof. Annica Black-Schaffer (Uppsala University)

11:45 → 13:00 Lunch Break

13:00 → 13:50 Quantum Simulations and Quantum Error Correction with Bosonic Modes

It is well-known that fermions are difficult to simulate with qubits because of their odd symmetry under
exchange. It is less widely appreciated that bosons, despite their even symmetry under exchange, are
also difficult to simulate with qubits. I will discuss how quantum hardware containing bosonic modes
(microwave resonators) offers great hardware efficiency for simulation of many-body and lattice gauge
models containing bosons. Time permitting, I will also discuss recent experimental success in quantum
error correction beyond the break-even point using the GKP bosonic code.

Speaker: Prof. Steve Girvin (Yale University)

Introduktion to Quantum Error Correction

13:50 → 14:10 Break

14:10 → 15:00 Quantum Simulations and Quantum Error Correction with Bosonic Modes

It is well-known that fermions are difficult to simulate with qubits because of their odd symmetry under
exchange. It is less widely appreciated that bosons, despite their even symmetry under exchange, are
also difficult to simulate with qubits. I will discuss how quantum hardware containing bosonic modes
(microwave resonators) offers great hardware efficiency for simulation of many-body and lattice gauge
models containing bosons. Time permitting, I will also discuss recent experimental success in quantum
error correction beyond the break-even point using the GKP bosonic code.

Speaker: Prof. Steve Girvin (Yale University)

15:00 → 15:30 Coffee Break

15:30 → 16:20 Exceptional Topology of Non-Hermitian Systems

Non-Hermitian “Hamiltonians” occur in the effective description of various physical settings ranging from classical photonics to quantum materials. Using simple examples, I will discuss topological aspects of such systems related to the non-Hermitian concept of exceptional degeneracies at which both eigenvalues and eigenvectors coalesce. I will also discuss how the bulk-boundary correspondence is modified in non-Hermitian systems and how this might be harnessed in novel sensor devices.

Speaker: Prof. Emil Bergholtz (Stockholm University)

Exceptional Topology of Non-Hermitian Systems

16:20 → 16:40 Break

16:40 → 17:30 Exceptional Topology of Non-Hermitian Systems

Non-Hermitian “Hamiltonians” occur in the effective description of various physical settings ranging from classical photonics to quantum materials. Using simple examples, I will discuss topological aspects of such systems related to the non-Hermitian concept of exceptional degeneracies at which both eigenvalues and eigenvectors coalesce. I will also discuss how the bulk-boundary correspondence is modified in non-Hermitian systems and how this might be harnessed in novel sensor devices.

Speaker: Prof. Emil Bergholtz (Stockholm University)

17:30 → 17:45 Break

17:45 → 18:30 Q&A: with Black-Schaffer, Girvin, Bergholtz

Question and answer session with the lecturers.

19:00 → 21:00 Dinner and social activities

Saturday 18 June

09:15 → 10:15 In two and one spatial dimensions...

In two and one spatial dimensions, we have the possibility of anyon statistics, that is, quantum statistics of identical particles which interpolates between the canonical choices of fermions and bosons. The mathematical reason is that in a path integral formulation, the group describing interchanges is not the permutation, but the braid group, which, in two dimensions, has a continuum of one-dimensional representation labeled by a U(1) phase parameter θ.
Physically, this statistical parameter describes the phase acquired by the wave function as we interchange two anyons by winding them counterclockwise around each other. This phase leads to a fractional shift in the allowed values for the relative angular momenta.
Anyons can be realized by composites consisting of electric charge and infinitesimally thin magnetic flux tubes. Restrictions for fractional statistics on closed surfaces can be traced back to
Dirac’s monopole condition. In field theory, statistical transmutations, and in particular anyon statistics, can be implemented very naturally by a Chern-Simons term in a fictitious gauge field, which attaches both charge and flux tubes to the particles.
The quasi particle excitations of fractionally quantized Hall states obey anyon statistics. In one dimension, the crossings of anyons on a ring are always uni-directional, such that a fractional phase θ acquired upon interchange gives rise to fractional shifts in the relative momenta between the anyons. In non-Abelian generalizations, anyons span an internal space of (degenerate) states and transform under higher dimensional representations of the braid group as we wind them around each other. Since the internal state vector is insensitive to local perturbations, non-Abelian anyons may prove instrumental in the construction of fault-tolerant quantum computers.

Speaker: Prof. Martin Greiter (Julius-Maximilians-Universität)

10:15 → 10:30 Coffee Break

10:30 → 11:30 In two and one spatial dimensions...

In two and one spatial dimensions, we have the possibility of anyon statistics, that is, quantum statistics of identical particles which interpolates between the canonical choices of fermions and bosons. The mathematical reason is that in a path integral formulation, the group describing interchanges is not the permutation, but the braid group, which, in two dimensions, has a continuum of one-dimensional representation labeled by a U(1) phase parameter θ.
Physically, this statistical parameter describes the phase acquired by the wave function as we interchange two anyons by winding them counterclockwise around each other. This phase leads to a fractional shift in the allowed values for the relative angular momenta.
Anyons can be realized by composites consisting of electric charge and infinitesimally thin magnetic flux tubes. Restrictions for fractional statistics on closed surfaces can be traced back to
Dirac’s monopole condition. In field theory, statistical transmutations, and in particular anyon statistics, can be implemented very naturally by a Chern-Simons term in a fictitious gauge field, which attaches both charge and flux tubes to the particles.
The quasi particle excitations of fractionally quantized Hall states obey anyon statistics. In one dimension, the crossings of anyons on a ring are always uni-directional, such that a fractional phase θ acquired upon interchange gives rise to fractional shifts in the relative momenta between the anyons. In non-Abelian generalizations, anyons span an internal space of (degenerate) states and transform under higher dimensional representations of the braid group as we wind them around each other. Since the internal state vector is insensitive to local perturbations, non-Abelian anyons may prove instrumental in the construction of fault-tolerant quantum computers.

Speaker: Prof. Martin Greiter (Julius-Maximilians-Universität)

11:45 → 19:45 Social activities - Excursion (please see the e-mail sent from us for the details)

Sunday 19 June

09:00 → 21:00 Free time (please see the notes for the details)

On Sunday we will have no activities and you are free to make any arrangement on your own.

Breakfast will be served by the hotel as usual, but no lunch and dinner will be served for those who decide to stay at the hotel. You are responsible for your meals on Sunday.

Monday 20 June

09:30 → 10:30 Time Reversal Symmetry and Its Breaking

I will give two lectures centered on time reversal symmetry T and its breaking. The overwhelming emphasis will be on non-dissipative dynamics.
In the first lecture, after briefly reviewing time reversal symmetry in classical physics and elementary quantum mechanics, I will turn to the issue of T in the standard model. I will derive the “main theorem of the standard model”, which puts the interactions allowed by general principles into a simple canonical form. This will pinpoint the origin of observed fundamental T violation and the motivation for Peccei-Quinn symmetry and axion physics.
In the second lecture I will discuss, mainly through a couple of case studies, how T symmetry figures into the analysis of matter. Specifically, I will discuss a canonical model of charge fractionalization (inspired by polyacetylene) and the issue of whether biology might have, in addition to its well-known chirality, also “temporal chirality”. The systematic use of effective Lagrangians will be a unifying pedagogical theme.

Speaker: Prof. Frank Wilczek (Stockholm University)

T Symmetry and Its Violation Part1. Fundamentals

10:30 → 10:45 Coffee Break

10:45 → 11:45 Time Reversal Symmetry and Its Breaking

I will give two lectures centered on time reversal symmetry T and its breaking. The overwhelming emphasis will be on non-dissipative dynamics.
In the first lecture, after briefly reviewing time reversal symmetry in classical physics and elementary quantum mechanics, I will turn to the issue of T in the standard model. I will derive the “main theorem of the standard model”, which puts the interactions allowed by general principles into a simple canonical form. This will pinpoint the origin of observed fundamental T violation and the motivation for Peccei-Quinn symmetry and axion physics.
In the second lecture I will discuss, mainly through a couple of case studies, how T symmetry figures into the analysis of matter. Specifically, I will discuss a canonical model of charge fractionalization (inspired by polyacetylene) and the issue of whether biology might have, in addition to its well-known chirality, also “temporal chirality”. The systematic use of effective Lagrangians will be a unifying pedagogical theme.

Speaker: Prof. Frank Wilczek (Stockholm University)

11:45 → 13:00 Lunch Break

13:00 → 13:50 Superoscillations old and new

This concerns a substantial and fast-developing area, in which the concept of functions that vary faster than they should connects a number of subjects conventionally regarded as separate: quantum physics, optical singularities, mathematical function theory, superresolution microscopy, radar theory... The connections provide a wonderful illustration of the unity of different areas of mathematics and physics.
F.C. Frank: “Physics is not just Concerning the Nature of Things, but Concerning the Interconnectedness of all the Natures of Things”

Speaker: Prof. Michael Berry (University of Bristol)

13:50 → 14:10 Break

14:10 → 15:00 Superoscillations old and new

This concerns a substantial and fast-developing area, in which the concept of functions that vary faster than they should connects a number of subjects conventionally regarded as separate: quantum physics, optical singularities, mathematical function theory, superresolution microscopy, radar theory... The connections provide a wonderful illustration of the unity of different areas of mathematics and physics.
F.C. Frank: “Physics is not just Concerning the Nature of Things, but Concerning the Interconnectedness of all the Natures of Things”

Speaker: Prof. Michael Berry (University of Bristol)

15:00 → 15:30 Coffee Break

15:30 → 16:20 A beginners guide to wavelike dark matter experiments

I will introduce wavelike dark matter, with a particular emphasis on axions, axion-like particles and hidden photons. I will outline the primary search strategies (experimental, astrophysical and cosmological) and explore many of the recent developments in the experimental landscape. Finally, I will go through a pedagogical example of a new kind of experiment, with emphasis on the development process rather than physics.

Speaker: Dr Alexander Millar (Stockholm University)

Searching for Wavelike Dark Matter: The Theory

16:20 → 16:40 Break

16:40 → 17:30 A beginners guide to wavelike dark matter experiments

I will introduce wavelike dark matter, with a particular emphasis on axions, axion-like particles and hidden photons. I will outline the primary search strategies (experimental, astrophysical and cosmological) and explore many of the recent developments in the experimental landscape. Finally, I will go through a pedagogical example of a new kind of experiment, with emphasis on the development process rather than physics.

Speaker: Dr Alexander Millar (Stockholm University)

Searching for Wavelike Dark Matter: The Interactions

17:30 → 17:45 Break

17:45 → 18:30 Q&A: with Wilczek, Berry, Millar, Greiter

Question and answer session with the lecturers.

19:00 → 20:00 Dinner

21:00 → 23:00 Watch movie together

Tuesday 21 June

09:30 → 10:30 Metamaterials: from left-handed media to hyperbolic metamaterials

The metamaterials are artificially created materials with electromagnetic properties not readily available in natural media. The metamaterials allow to control electromagnetic waves in unprecedented ways: one can create flat lenses with subwavelength resolution, dramatically modify spontaneous emission of quantum sources via Purcell effect, negatively refract plane waves and invert phase velocity of light. These effects which seemed impossible for a long time now become common and many new devices start to employ them. The special kind of metamaterials, so-called wire medtamaterials are composed of metallic wires and behave as artificial plasma and feature effects of strong spatial dispersion not observable in any other media. The wire media have found tremendous number of application ranging from magnetic resonance imaging to axion detection. The evolution of metamaterials also led to wide use of their 2d counterparts – metasurfaces. With the help of these planar artificial interfaces one can rotate polarization, filter, refract, focus and localize electromagnetic waves and build many functional devices for variety of diverse applications. Basically, the metamaterials and metasurfaces opened a fundamentally new way to manipulation of electromagnetic waves.

Speaker: Prof. Pavel Belov (ITMO University)

10:30 → 10:45 Coffee Break

10:45 → 11:45 Metamaterials: from left-handed media to hyperbolic metamaterials

The metamaterials are artificially created materials with electromagnetic properties not readily available in natural media. The metamaterials allow to control electromagnetic waves in unprecedented ways: one can create flat lenses with subwavelength resolution, dramatically modify spontaneous emission of quantum sources via Purcell effect, negatively refract plane waves and invert phase velocity of light. These effects which seemed impossible for a long time now become common and many new devices start to employ them. The special kind of metamaterials, so-called wire medtamaterials are composed of metallic wires and behave as artificial plasma and feature effects of strong spatial dispersion not observable in any other media. The wire media have found tremendous number of application ranging from magnetic resonance imaging to axion detection. The evolution of metamaterials also led to wide use of their 2d counterparts – metasurfaces. With the help of these planar artificial interfaces one can rotate polarization, filter, refract, focus and localize electromagnetic waves and build many functional devices for variety of diverse applications. Basically, the metamaterials and metasurfaces opened a fundamentally new way to manipulation of electromagnetic waves.

Speaker: Prof. Pavel Belov (ITMO University)

11:45 → 13:00 Lunch Break

13:00 → 13:50 A beginners guide to wavelike dark matter experiments

I will introduce wavelike dark matter, with a particular emphasis on axions, axion-like particles and hidden photons. I will outline the primary search strategies (experimental, astrophysical and cosmological) and explore many of the recent developments in the experimental landscape. Finally, I will go through a pedagogical example of a new kind of experiment, with emphasis on the development process rather than physics.

Speaker: Dr Alexander Millar (Stockholm University)

Searching for Wavelike Dark Matter: The Experiments

13:50 → 14:10 Break

14:10 → 15:00 A beginners guide to wavelike dark matter experiments

I will introduce wavelike dark matter, with a particular emphasis on axions, axion-like particles and hidden photons. I will outline the primary search strategies (experimental, astrophysical and cosmological) and explore many of the recent developments in the experimental landscape. Finally, I will go through a pedagogical example of a new kind of experiment, with emphasis on the development process rather than physics.

Speaker: Dr Alexander Millar (Stockholm University)

Searching for Wavelike Dark Matter: An Example

15:00 → 15:30 Coffee Break

15:30 → 16:20 Time Reversal Symmetry and Its Breaking

I will give two lectures centered on time reversal symmetry T and its breaking. The overwhelming emphasis will be on non-dissipative dynamics.
In the first lecture, after briefly reviewing time reversal symmetry in classical physics and elementary quantum mechanics, I will turn to the issue of T in the standard model. I will derive the “main theorem of the standard model”, which puts the interactions allowed by general principles into a simple canonical form. This will pinpoint the origin of observed fundamental T violation and the motivation for Peccei-Quinn symmetry and axion physics.
In the second lecture I will discuss, mainly through a couple of case studies, how T symmetry figures into the analysis of matter. Specifically, I will discuss a canonical model of charge fractionalization (inspired by polyacetylene) and the issue of whether biology might have, in addition to its well-known chirality, also “temporal chirality”. The systematic use of effective Lagrangians will be a unifying pedagogical theme.

Speaker: Prof. Frank Wilczek (Stockholm University)

T Symmetry and Its Violation Part1. Fundamentals

16:20 → 16:40 Break

16:40 → 17:30 Time Reversal Symmetry and Its Breaking

I will give two lectures centered on time reversal symmetry T and its breaking. The overwhelming emphasis will be on non-dissipative dynamics.
In the first lecture, after briefly reviewing time reversal symmetry in classical physics and elementary quantum mechanics, I will turn to the issue of T in the standard model. I will derive the “main theorem of the standard model”, which puts the interactions allowed by general principles into a simple canonical form. This will pinpoint the origin of observed fundamental T violation and the motivation for Peccei-Quinn symmetry and axion physics.
In the second lecture I will discuss, mainly through a couple of case studies, how T symmetry figures into the analysis of matter. Specifically, I will discuss a canonical model of charge fractionalization (inspired by polyacetylene) and the issue of whether biology might have, in addition to its well-known chirality, also “temporal chirality”. The systematic use of effective Lagrangians will be a unifying pedagogical theme.

Speaker: Prof. Frank Wilczek (Stockholm University)

T Symmetry and Its Violation Part 2. Some Phenomenology

17:30 → 17:45 Break

17:45 → 18:30 Q&A: with Belov, Millar, Wilczek

Question and answer session with the lecturers.

19:00 → 20:00 Dinner

21:00 → 23:00 Watch movie together

Wednesday 22 June

09:30 → 10:30 Metamaterials: from left-handed media to hyperbolic metamaterials

The metamaterials are artificially created materials with electromagnetic properties not readily available in natural media. The metamaterials allow to control electromagnetic waves in unprecedented ways: one can create flat lenses with subwavelength resolution, dramatically modify spontaneous emission of quantum sources via Purcell effect, negatively refract plane waves and invert phase velocity of light. These effects which seemed impossible for a long time now become common and many new devices start to employ them. The special kind of metamaterials, so-called wire medtamaterials are composed of metallic wires and behave as artificial plasma and feature effects of strong spatial dispersion not observable in any other media. The wire media have found tremendous number of application ranging from magnetic resonance imaging to axion detection. The evolution of metamaterials also led to wide use of their 2d counterparts – metasurfaces. With the help of these planar artificial interfaces one can rotate polarization, filter, refract, focus and localize electromagnetic waves and build many functional devices for variety of diverse applications. Basically, the metamaterials and metasurfaces opened a fundamentally new way to manipulation of electromagnetic waves.

Speaker: Prof. Pavel Belov (ITMO University)

10:30 → 10:45 Coffee Break

10:45 → 11:45 Metamaterials: from left-handed media to hyperbolic metamaterials

The metamaterials are artificially created materials with electromagnetic properties not readily available in natural media. The metamaterials allow to control electromagnetic waves in unprecedented ways: one can create flat lenses with subwavelength resolution, dramatically modify spontaneous emission of quantum sources via Purcell effect, negatively refract plane waves and invert phase velocity of light. These effects which seemed impossible for a long time now become common and many new devices start to employ them. The special kind of metamaterials, so-called wire medtamaterials are composed of metallic wires and behave as artificial plasma and feature effects of strong spatial dispersion not observable in any other media. The wire media have found tremendous number of application ranging from magnetic resonance imaging to axion detection. The evolution of metamaterials also led to wide use of their 2d counterparts – metasurfaces. With the help of these planar artificial interfaces one can rotate polarization, filter, refract, focus and localize electromagnetic waves and build many functional devices for variety of diverse applications. Basically, the metamaterials and metasurfaces opened a fundamentally new way to manipulation of electromagnetic waves.

Speaker: Prof. Pavel Belov (ITMO University)

11:45 → 13:00 Lunch Break

13:00 → 13:50 Quantum Steampunk: The Physics of Yesterday’s Tomorrow

Thermodynamics has shed light on engines, efficiency, and time’s arrow since the Industrial Revolution. But the steam engines that powered the Industrial Revolution were large and classical. Much of today’s technology and experiments are small-scale, quantum, far from equilibrium, and processing information. Nineteenth-century thermodynamics needs re-envisioning for the 21st century. Guidance has come from the mathematical toolkit of quantum information theory. Applying quantum information theory to thermodynamics sheds light on fundamental questions (e.g., how does entanglement spread during quantum thermalization? How can we distinguish quantum heat from quantum work?) and practicalities (e.g., quantum engines and the thermodynamic value of coherences). I will overview how quantum information theory is being used to revolutionize Thermodynamics.

Speaker: Prof. Nicole Yunger Halpern (University of Maryland - College Park)

13:50 → 14:10 Break

14:10 → 15:00 Quantum Steampunk: The Physics of Yesterday’s Tomorrow

Thermodynamics has shed light on engines, efficiency, and time’s arrow since the Industrial Revolution. But the steam engines that powered the Industrial Revolution were large and classical. Much of today’s technology and experiments are small-scale, quantum, far from equilibrium, and processing information. Nineteenth-century thermodynamics needs re-envisioning for the 21st century. Guidance has come from the mathematical toolkit of quantum information theory. Applying quantum information theory to thermodynamics sheds light on fundamental questions (e.g., how does entanglement spread during quantum thermalization? How can we distinguish quantum heat from quantum work?) and practicalities (e.g., quantum engines and the thermodynamic value of coherences). I will overview how quantum information theory is being used to revolutionize Thermodynamics.

Speaker: Prof. Nicole Yunger Halpern (University of Maryland - College Park)

15:00 → 15:30 Coffee Break

15:30 → 16:20 Superoscillations old and new

This concerns a substantial and fast-developing area, in which the concept of functions that vary faster than they should connects a number of subjects conventionally regarded as separate: quantum physics, optical singularities, mathematical function theory, superresolution microscopy, radar theory... The connections provide a wonderful illustration of the unity of different areas of mathematics and physics.
F.C. Frank: “Physics is not just Concerning the Nature of Things, but Concerning the Interconnectedness of all the Natures of Things”

Speaker: Prof. Michael Berry (University of Bristol)

16:20 → 16:40 Break

16:40 → 17:30 Superoscillations old and new

This concerns a substantial and fast-developing area, in which the concept of functions that vary faster than they should connects a number of subjects conventionally regarded as separate: quantum physics, optical singularities, mathematical function theory, superresolution microscopy, radar theory... The connections provide a wonderful illustration of the unity of different areas of mathematics and physics.
F.C. Frank: “Physics is not just Concerning the Nature of Things, but Concerning the Interconnectedness of all the Natures of Things”

Speaker: Prof. Michael Berry (University of Bristol)

17:30 → 17:45 Break

17:45 → 18:30 Q&A: with Belov, Yunger Halpern, Berry

Question and answer session with the lecturers.

18:30 → 21:00 Dinner (BBQ) and Pool + Spa

Thursday 23 June

09:30 → 10:30 Quantum Sensing and Metrology

Quantum sensing" describes the use of a quantum system, quantum properties or quantum phenomena to perform a measurement of a physical quantity.
More recently, quantum sensing has become a distinct and rapidly growing branch of research within the area of quantum science and technology, with the most common platforms being spin qubits, trapped ions and flux qubits.
Quantum sensors can surpass the sensitivity of classical devices, and their ultimate performance is studied in quantum metrology. In addition, quantum sensors can be used to characterize the noise created by their environment, and thus guide the development of error correction strategies.
In these lectures, I will provide an introduction to the basic principles, methods and concepts of quantum sensing and metrology.

Speaker: Prof. Paola Cappellaro (Massachusetts Institute of Technology)

10:30 → 10:45 Coffee Break

10:45 → 11:45 Quantum Sensing and Metrology

Quantum sensing" describes the use of a quantum system, quantum properties or quantum phenomena to perform a measurement of a physical quantity.
More recently, quantum sensing has become a distinct and rapidly growing branch of research within the area of quantum science and technology, with the most common platforms being spin qubits, trapped ions and flux qubits.
Quantum sensors can surpass the sensitivity of classical devices, and their ultimate performance is studied in quantum metrology. In addition, quantum sensors can be used to characterize the noise created by their environment, and thus guide the development of error correction strategies.
In these lectures, I will provide an introduction to the basic principles, methods and concepts of quantum sensing and metrology.

Speaker: Prof. Paola Cappellaro (Massachusetts Institute of Technology)

11:45 → 13:00 Lunch Break

13:00 → 13:50 Quantum advantage and quantum simulation with photons and atoms. (via Zoom)

Quantum computation harnesses the collective properties of quantum states, such as superposition, interference, and entanglement, to perform calculations, can greatly enhance the computing power. Physically, there are many candidates of quantum systems to implement quantum computation and simulation. In this lecture, I will introduce quantum computation and simulation with photons and cold atoms.
By developing high-performance quantum light sources, the multi-photon interference has been scaled up to implement boson sampling with up to 76 photons out of a 100-mode interferometer, which yields a Hilbert state space dimension of 1030 and a rate that is 1014 faster than using the state-of-the-art simulation strategy on supercomputers. Such a demonstration of quantum computational advantage is a much-anticipated milestone for quantum computing. The special-purpose photonic platform will be further used to investigate practical applications linked to the Gaussian boson sampling, such as graph optimization and quantum machine learning.
Ultracold atoms constitute a unique physical system for studying strongly correlated quantum many-body physics, and promise a great potential for quantum simulation. A new method of staggered-immersion cooling has been demonstrated in experiment leading to dramatic reduction of defects (from 10% to 0.8%) in a 2D lattice of 10k sites. Based on this, 1250 pairs of entangled atoms are prepared with a fidelity of 99.3%. This well-controlled quantum system consisting 71 lattice sites is used to model the Hamiltonian of a 1D lattice gauge theory with gauge symmetry of U(1), the Schwinger model. Furthermore, the properties of LGTs, such as quantum thermalization, have been studied. It is expected that, quantum simulation tasks outperforming relevant numerical calculations with classical supercomputers are likely to be demonstrated with the state-of-the-art cold-atom quantum simulators.

Speakers: Prof. Jianwei Pan (University of Science and Technology of China), Prof. Yuao Chen (University of Science and Technology of China)

13:50 → 14:10 Break

14:10 → 15:00 Quantum advantage and quantum simulation with photons and atoms. (via Zoom)

Quantum computation harnesses the collective properties of quantum states, such as superposition, interference, and entanglement, to perform calculations, can greatly enhance the computing power. Physically, there are many candidates of quantum systems to implement quantum computation and simulation. In this lecture, I will introduce quantum computation and simulation with photons and cold atoms.
By developing high-performance quantum light sources, the multi-photon interference has been scaled up to implement boson sampling with up to 76 photons out of a 100-mode interferometer, which yields a Hilbert state space dimension of 1030 and a rate that is 1014 faster than using the state-of-the-art simulation strategy on supercomputers. Such a demonstration of quantum computational advantage is a much-anticipated milestone for quantum computing. The special-purpose photonic platform will be further used to investigate practical applications linked to the Gaussian boson sampling, such as graph optimization and quantum machine learning.
Ultracold atoms constitute a unique physical system for studying strongly correlated quantum many-body physics, and promise a great potential for quantum simulation. A new method of staggered-immersion cooling has been demonstrated in experiment leading to dramatic reduction of defects (from 10% to 0.8%) in a 2D lattice of 10k sites. Based on this, 1250 pairs of entangled atoms are prepared with a fidelity of 99.3%. This well-controlled quantum system consisting 71 lattice sites is used to model the Hamiltonian of a 1D lattice gauge theory with gauge symmetry of U(1), the Schwinger model. Furthermore, the properties of LGTs, such as quantum thermalization, have been studied. It is expected that, quantum simulation tasks outperforming relevant numerical calculations with classical supercomputers are likely to be demonstrated with the state-of-the-art cold-atom quantum simulators.

Speakers: Prof. Jianwei Pan (University of Science and Technology of China), Prof. Yuao Chen (University of Science and Technology of China)

15:00 → 15:30 Coffee Break

15:30 → 16:20 Dynamics of emergent gauge theories, false vacuums and virtual particles. (via Zoom)

Emergent gauge theories are ubiquitous in modern condensed matter physics under various forms such as quantum spin liquids. I will provide an introduction to how they arise, and the novel dynamics possible in them due to key differences in energy scales compared to the usual gauge theories of high energy physics.

In the second part of the lecture, using a simple Ising model as a prototype, I will discuss some tell-tale signatures of how we can know if we are in a false vacuum universe even if the actual decay to the true vacuum takes an absurdly long time. This will illustrate some observable signatures of the dynamics of virtual particles popping in and out of existence.

Speaker: Dr Sid Morampudi (Massachusetts Institute of Technology)

16:20 → 16:30 Break

16:30 → 17:30 Dynamics of emergent gauge theories, false vacuums and virtual particles. (via Zoom)

Emergent gauge theories are ubiquitous in modern condensed matter physics under various forms such as quantum spin liquids. I will provide an introduction to how they arise, and the novel dynamics possible in them due to key differences in energy scales compared to the usual gauge theories of high energy physics.

In the second part of the lecture, using a simple Ising model as a prototype, I will discuss some tell-tale signatures of how we can know if we are in a false vacuum universe even if the actual decay to the true vacuum takes an absurdly long time. This will illustrate some observable signatures of the dynamics of virtual particles popping in and out of existence.

Speaker: Dr Sid Morampudi (Massachusetts Institute of Technology)

17:30 → 17:45 Break

17:45 → 18:30 Q&A: with Cappellaro, Pan, Chen, Morampudi

Question and answer session with the lecturers.

19:00 → 20:00 Dinner

Friday 24 June

09:30 → 10:30 ?

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Speaker: Prof. Paola Cappellaro (Massachusetts Institute of Technology)

10:30 → 10:45 Coffee Break

10:45 → 11:30 ?

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Speaker: Prof. Paola Cappellaro (Massachusetts Institute of Technology)

11:30 → 12:30 Lunch Break

12:30 → 13:30 Exceptional Topology of Non-Hermitian Systems

Non-Hermitian “Hamiltonians” occur in the effective description of various physical settings ranging from classical photonics to quantum materials. Using simple examples, I will discuss topological aspects of such systems related to the non-Hermitian concept of exceptional degeneracies at which both eigenvalues and eigenvectors coalesce. I will also discuss how the bulk-boundary correspondence is modified in non-Hermitian systems and how this might be harnessed in novel sensor devices.

Speaker: Prof. Emil Bergholtz (Stockholm University)

13:30 → 13:40 Break

13:40 → 14:30 Exceptional Topology of Non-Hermitian Systems

Non-Hermitian “Hamiltonians” occur in the effective description of various physical settings ranging from classical photonics to quantum materials. Using simple examples, I will discuss topological aspects of such systems related to the non-Hermitian concept of exceptional degeneracies at which both eigenvalues and eigenvectors coalesce. I will also discuss how the bulk-boundary correspondence is modified in non-Hermitian systems and how this might be harnessed in novel sensor devices.

Speaker: Prof. Emil Bergholtz (Stockholm University)

14:30 → 14:40 Break

14:40 → 15:30 Quantum advantage and quantum simulation with photons and atoms. (via Zoom)

Quantum computation harnesses the collective properties of quantum states, such as superposition, interference, and entanglement, to perform calculations, can greatly enhance the computing power. Physically, there are many candidates of quantum systems to implement quantum computation and simulation. In this lecture, I will introduce quantum computation and simulation with photons and cold atoms.
By developing high-performance quantum light sources, the multi-photon interference has been scaled up to implement boson sampling with up to 76 photons out of a 100-mode interferometer, which yields a Hilbert state space dimension of 1030 and a rate that is 1014 faster than using the state-of-the-art simulation strategy on supercomputers. Such a demonstration of quantum computational advantage is a much-anticipated milestone for quantum computing. The special-purpose photonic platform will be further used to investigate practical applications linked to the Gaussian boson sampling, such as graph optimization and quantum machine learning.
Ultracold atoms constitute a unique physical system for studying strongly correlated quantum many-body physics, and promise a great potential for quantum simulation. A new method of staggered-immersion cooling has been demonstrated in experiment leading to dramatic reduction of defects (from 10% to 0.8%) in a 2D lattice of 10k sites. Based on this, 1250 pairs of entangled atoms are prepared with a fidelity of 99.3%. This well-controlled quantum system consisting 71 lattice sites is used to model the Hamiltonian of a 1D lattice gauge theory with gauge symmetry of U(1), the Schwinger model. Furthermore, the properties of LGTs, such as quantum thermalization, have been studied. It is expected that, quantum simulation tasks outperforming relevant numerical calculations with classical supercomputers are likely to be demonstrated with the state-of-the-art cold-atom quantum simulators.

Speakers: Prof. Jianwei Pan (University of Science and Technology of China), Prof. Yuao Chen (University of Science and Technology of China)

15:30 → 15:50 Break

15:50 → 16:40 Quantum advantage and quantum simulation with photons and atoms. (via Zoom)

Quantum computation harnesses the collective properties of quantum states, such as superposition, interference, and entanglement, to perform calculations, can greatly enhance the computing power. Physically, there are many candidates of quantum systems to implement quantum computation and simulation. In this lecture, I will introduce quantum computation and simulation with photons and cold atoms.
By developing high-performance quantum light sources, the multi-photon interference has been scaled up to implement boson sampling with up to 76 photons out of a 100-mode interferometer, which yields a Hilbert state space dimension of 1030 and a rate that is 1014 faster than using the state-of-the-art simulation strategy on supercomputers. Such a demonstration of quantum computational advantage is a much-anticipated milestone for quantum computing. The special-purpose photonic platform will be further used to investigate practical applications linked to the Gaussian boson sampling, such as graph optimization and quantum machine learning.
Ultracold atoms constitute a unique physical system for studying strongly correlated quantum many-body physics, and promise a great potential for quantum simulation. A new method of staggered-immersion cooling has been demonstrated in experiment leading to dramatic reduction of defects (from 10% to 0.8%) in a 2D lattice of 10k sites. Based on this, 1250 pairs of entangled atoms are prepared with a fidelity of 99.3%. This well-controlled quantum system consisting 71 lattice sites is used to model the Hamiltonian of a 1D lattice gauge theory with gauge symmetry of U(1), the Schwinger model. Furthermore, the properties of LGTs, such as quantum thermalization, have been studied. It is expected that, quantum simulation tasks outperforming relevant numerical calculations with classical supercomputers are likely to be demonstrated with the state-of-the-art cold-atom quantum simulators.

Speakers: Prof. Jianwei Pan (University of Science and Technology of China), Prof. Yuao Chen (University of Science and Technology of China)

16:40 → 20:00 Closing ceremony and midsummer celebration

Saturday 25 June

07:00 → 12:00 Check-out