Bootstrapping the stationary state of bosonic open quantum systems
Phys. Rev. A 113, 062440 – Published 16 June, 2026
DOI: https://doi.org/10.1103/5db2-q49l
Abstract
We propose a method to compute expectation values of observables in the stationary state of a (Markovian) bosonic open quantum system. Using a hierarchy of semidefinite relaxations, we obtain finer and finer upper and lower bounds to any expectation value of interest. The bounds are rigorous, robust to stationary state degeneracies, and numerically improve as the occupation number increases on the examples we considered. This makes it adapted to the simulation of stationary states of bosonic qubits and, in particular, dissipatively stabilized cat qubits.
