Speaker
Dr
Andre Eckardt
(MPIPKS Dresden)
Description
In the last decade there has been considerable progress in
the experimental realization of artificial many-body systems
made of ultracold neutral atoms in optical lattices potentials.
These systems are extremely clean, well isolated from their
environment, and highly tunable (also during the
experiment). This makes them a flexible platform for
engineering many-body quantum physics in and also out-of
equilibirum. An important ingredient is the abilty to create
artificial gauge potentials that allow to mimic strong
magnetic fields. Here one aim is to realize quantum Hall-
type physics in the regime where the length scale of the
lattice matters, like in the strong-field regime (captured by
the Harper model) or like in topological insualtors were
appropriately chosen staggered fields lead to a quantized
Hall conductivity for a completely filled band. Pioneering
experiments in which artificial gauge potentials have been
created in optical lattices have been reported recently by
Aidelsburger et al. (PRL 2011), Jimenez-Garcia et al. (PRL
2012), and Struck et al. (Science 2011, PRL 2012).
I will talk about the theory behind the approach of Struck et
al. where a gauge potential is induced dynamically by fast
lattice shaking [see also Eckardt et al. EPL 2010, Hauke et
al. PRL 2012]. The shaken lattice is a Floquet-system and
its dynamics is captured by an effective time-independent
Hamiltonian that is obtained by integrating out the rapid
dynamics within a period of the forcing. Temporal
symmetries are indientified that have to be broken in order
to achieve tunable gauge potentials. I will also discuss
applications of this method, for example how it can be used
to realize a topological insulator and how it can be
generalized to create non-abelian gauge fields in spin-
dependent lattices.
Author
Dr
Andre Eckardt
(MPIPKS Dresden)
