The driven-dissipative nonlinear photon systems provide a promising platform to model the nonequilibrium quantum phase transitions. However, the critical property of such a phase transition has remained elusive. With the scaling theory, we accurately measure the critical point and critical exponents of the second-order quantum phase transition in a bosonic mode with a Kerr nonlinearity. The results show that the dissipative phase transition exhibits a weak universality class, in which the universality classes of the close and open quantum Rabi models in the previous studies are both included. Further, one may understand the spatial dimension $d=1$ and the correlation length from the photon occupation probability distribution. When coupled to a quantum-dot electronic circuit, such quantum criticality can be detected by a simple transport signature. As an application, the photocurrent in an unbiased quantum dot system can be significantly enhanced near the phase transition.

Close

PrevNext

View figure in article

• Open quantum systems
• Quantum criticality
• Quantum phase transitions
• Bose-Hubbard model
• Quantum master equation