Nonperturbative Switching Rates in Bistable Open Quantum Systems: From Driven Kerr Oscillators to Dissipative Cat Qubits

In this Letter, we use path integral techniques to predict the switching rate in a single-mode bistable open quantum system. While analytical expressions are well-known to be accessible for systems subject to Gaussian noise obeying classical detailed balance, we extend this approach to a class of open quantum systems, those which satisfy the recently introduced notion of hidden time-reversal symmetry [D. Roberts et al., PRX Quantum 2, 020336 (2021)2691-339910.1103/PRXQuantum.2.020336]. In particular, in the context of quantum computing, we obtain analytical estimates of bit-flip error rates in cat-qubit architectures. We confirm these findings by comparing our results to numerically exact diagonalization of the Lindbladian. Our results provide a path towards exploring switching phenomena in multistable open quantum systems.