2016/08/31 by Wim Casteels, Rosario Fazio, Cristiano Ciuti · 1 citation
Physics and Astronomy · #cond-mat.quant-gas #quant-ph
paper · pdf · doi:10.1103/physreva.95.012128
published as Phys. Rev. A 95, 012128 (2017) · revised version accepted for publication in PRA
arxiv created 2017/01/17 · arxiv updated 2017/01/24
We theoretically investigate the critical properties of a single driven-dissipative nonlinear photon mode. In a well-defined thermodynamical limit of large excitation numbers, the exact quantum solution describes a first-order phase transition in the regime where semiclassical theory predicts optical bistability. We study the behavior of the complex spectral gap associated with the Liouvillian superoperator of the corresponding master equation. We show that in this limit the Liouvillian gap vanishes exponentially and that the bimodality of the photon Wigner function disappears. The connection between the considered thermodynamical limit of large photon numbers for the single-mode cavity and the thermodynamical limit of many cavities for a driven-dissipative Bose-Hubbard system is discussed.