Protecting a bosonic qubit with autonomous quantum error correction II – Experiment

Existing demonstrations of quantum error correction are based on an active schedule of measurement and recovery operations which is hardware intensive and incurs additional error overhead. It is theoretically possible to correct quantum errors using dissipation in a continuous and autonomous fashion, without a classical controller. While dissipative confinement of a quantum system to a two-state manifold had been demonstrated, so far it has remained challenging to achieve a dissipation operator that counters the dominant natural errors in order to extend the lifetime of an encoded qubit. Here we present an autonomous error correction scheme for a bosonic qubit in a superconducting cavity, which directly corrects the dominant error channel of the system: single photon loss. In this Part II of the talk, we present our circuit QED setup and experimental results.