Alan A. Dzhioev, D. S. Kosov
We develop configuration interaction method to treat far from equilibrium quantum many-body systems. The concept of embedding (buffer zones between the reservoirs and the correlated quantum system) is used to derive an exact master equation for the reduced density matrix. To enable the use of field theoretic methods we employ the superoperator techniques in Liouville-Fock space. Within the suggested method the exact steady-state density matrix is represented as a linear combination all possible nonequilibrium quasiparticle excitations built on the appropriate reference state. As an example we consider the electron transport through the system with electron-phonon interaction. Using approximate (truncated) expansion of the density matrix we obtain the linear system of equations for two-quasiparticle amplitudes. Then we compute the current and compare the result with other approaches. The current conserving property of the method is proved.
View original:
http://arxiv.org/abs/1302.6469
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