A nonequilibrium statistical quasi-particles thermofield theory

For open quantum systems, environmental dissipative effect can be represented by statistical quasi-particles, namely dissipatons. We exploit this fact to establish the dissipaton thermofield theory. The resulting generalized Langevin dynamics of absorptive and emissive thermofield operators are effectively noise–resolved. Some universal relations are then readily followed between a important class of nonequilibrium steady–state correlation functions. All these relations are vali-dated numerically. A simple corollary is the transport current expression, which exactly recovers the result obtained from the nonequilibrium Green’s function formalism.