Speaker
Description
Scalability remains one of the central challenges to achieve fault-tolerant quantum computation in trapped-ion systems. A modular approach, where multiple ion trap modules are interconnected using optical photons [1] is a promising route to tackle this endeavor. In this context, efficient coupling of ions to well-defined optical modes is essential for achieving the remote-entanglement rates required between modules. Cavity QED in the strong coupling regime [2,3], with applications such as efficient single photon sources [4], nodes for quantum communication [5], and non-linear optics at the quantum level [6], enables fast ion-photon entanglement generation with applications in quantum computing and networks. We report our plans and progress towards implementing such a system with barium ions.
Small mode volumes that are required for strong coupling between the ion and cavity can be obtained using fiber-based microcavities [7,8]. We discuss progress and challenges towards integrating microcavities in an ion trap for coupling to barium ion’s strong S-P transition at 493 nm, with the long-term goal of using ion-cavity modules as nodes of a quantum network or qubits of a quantum computer that can be entangled by using photonic flying qubits. Cavities operating at short wavelengths have been hampered by degradation in vacuum [9]. We present results showing stable cavity operation at 493 nm in vacuum at low circulating powers [10].
Further, we discuss a number of planned experiments, including fast generation of atom-photon entanglement, fast cavity-assisted state readout, and state readout in the dispersive regime. Additionally, we present our monolithic ion trap platform fabricated via selective laser-induced etching (SLE) with integrated fiber-based Fabry-Perot cavity (FFPC). Together, these represent the crucial step toward a cavity QED system with barium ions, contributing to the broader effort of building modular trapped-ion quantum computers.
Acknowledgements
This work was supported by JST Moonshot R&D Grant Number JPMJMS2063 and MEXT Quantum Lead Flagship Program (MEXT Q-LEAP) Grant Number 20181503.
References
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| Academic level | PhD student |
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