Non-stochastic matrix Schrödinger equation for open systems
arXiv:1408.6624 · doi:10.1063/1.4903829
Abstract
We propose an extension of the Schrödinger equation for a quantum system interacting with environment. This equation describes dynamics of auxiliary wave-functions , from which the system density matrix can be reconstructed as . We formulate a compatibility condition, which ensures that the reconstructed density satisfies a given quantum master equation for the system density. The resulting non-stochastic evolution equation preserves positive-definiteness of the system density and is applicable to both Markovian and non-Markovian system-bath treatments. Our formalism also resolves a long-standing problem of energy non-conservation in the time-dependent variational principle applied to mixed states of closed systems.
5 pages, 2 figures