Protocol for high fidelity readout in the photon blockade regime of circuit QED

Abstract

The driven-damped Jaynes-Cummings model in the regime of strong coupling is found to exhibit a coexistence between the quantum photon blockaded state and a quasi-coherent bright state. We characterize the slow time scales and the basin of attraction of these metastable states using full quantum simulations. This form of bistability can be useful for implementing a qubit readout scheme that does not require additional circuit elements. We propose a coherent control sequence that makes use of a simple linear chirp of drive amplitude and frequency as well as qubit frequency. By optimizing the parameters of the system and the control pulse we demonstrate theoretically very high readout fidelities (>98%) and high contrast, with experimentally realistic parameters for qubits implemented in the circuit QED architecture.

4 pages, 4 figures.

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Cited by in corpus (7)

• Observation of the photon-blockade breakdown phase transition
• Simultaneous bistability of qubit and resonator in circuit quantum electrodynamics
• Single-atom maser with engineered circuit for population inversion
• Quantum phase transitions in the driven dissipative Jaynes-Cummings oscillator: from the dispersive regime to resonance
• A Real-time Instanton Approach to Quantum Activation
• Model Order Reduction for Open Quantum Systems Based on Measurement-adapted Time-coarse Graining
• Quantum jumps in amplitude bistability: Tracking a coherent and invertible state localization