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arXiv · 2008.13560

Tunable Chiral Bound States with Giant Atoms

Xin Wang·Tao Liu·Anton Frisk Kockum·Hong-Rong Li·Franco Nori
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Abstract

We propose tunable chiral bound states in a system composed of superconducting giant atoms and a Josephson photonic-crystal waveguide (PCW), with no analog in other quantum setups. The chiral bound states arise due to interference in the nonlocal coupling of a giant atom to multiple points of the waveguide. The chirality can be tuned by changing either the atom-waveguide coupling or the external bias of the PCW. Furthermore, the chiral bound states can induce directional dipole-dipole interactions between multiple giant atoms coupling to the same waveguide. Our proposal is ready to be implemented in experiments with superconducting circuits, where it can be used as a tunable toolbox to realize topological phase transitions and quantum simulations.

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Xin Wang, Tao Liu, Anton Frisk Kockum, Hong-Rong Li, Franco Nori. 2020-08-31. Tunable Chiral Bound States with Giant Atoms. https://doi.org/10.1103/physrevlett.126.043602

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