Fig. 1: Full parity detection.
From: Experimental demonstration of continuous quantum error correction
a Three qubits in two cavities, with each cavity implementing a full parity measurement. Lower right: ideal phase responses of a coherent tone reflected off each cavity for different qubit states. The parity probe tones are centered on the odd-parity resonances. The phase space (IQ) plots show the ideal steady state reflected tone for the shown qubit configuration. Dashed circles are centered on all possible steady state responses. b Micrograph of the superconducting chip with three transmons and two joint readout resonators. Ri labels the resonators and Qj labels the qubits.
