Bit-flip errors in dissipative cat qubits: second-order perturbation theory

Abstract

Dissipative cat qubits are known for the exponential suppression of the bit-flip rate. However, there is significant discrepancy between experimental measurements and analytical predictions of the strength of the bit-flip suppression. In this paper we resolve this discrepancy for some of the perturbations, by developing a second-order perturbation theory on top of a nonlinear dissipative Lindbladian. Following this scheme, we derive an analytical expression for the exponentially small bit-flip rate due to single-photon loss, which shows good agreement with numerical simulations. We also apply our scheme to other perturbations, such as frequency detuning and the Z gate, and find the corresponding bit-flip rates, which also show good agreement with the numerical simulation.

References in corpus (4)

• Confining the state of light to a quantum manifold by engineered two-photon loss
• Fault-tolerant quantum computation against biased noise
• Moving beyond the transmon: Noise-protected superconducting quantum circuits
• Theory of quasiparticle-induced errors in driven-dissipative Schrödinger cat qubits

Cited by in corpus (5)

• Hybrid cat-transmon architecture for scalable, hardware-efficient quantum error correction
• Preserving phase coherence and linearity in cat qubits with exponential bit-flip suppression
• Unraveling the switching dynamics in a quantum double-well potential
• Viewing protected superconducting qubits through the lens of the cat qubit
• Non-perturbative switching rates in bistable open quantum systems: from driven Kerr oscillators to dissipative cat qubits