Chiral Cavity Quantum Electrodynamics

Understand

Cavity quantum electrodynamics, which explores the granularity of light by coupling a resonator to a nonlinear emitter, has played a foundational role in the development of modern quantum information science and technology.

• In parallel, the field of condensed matter physics has been revolutionized by the discovery of underlying topological robustness in the face of disorder, often arising from the breaking of time-reversal symmetry, as in the case of the quantum Hall effect.
• In this work, we explore for the first time cavity quantum electrodynamics of a transmon qubit in the topological vacuum of a Harper-Hofstadter topological lattice.
• To achieve this, we assemble a square lattice of niobium superconducting resonators and break time-reversal symmetry by introducing ferrimagnets before coupling the system to a single transmon qubit.