Department of Physics, Université Libre de Bruxelles, Brussels, Belgium.
J Phys Condens Matter. 2012 Jun 6;24(22):225304. doi: 10.1088/0953-8984/24/22/225304. Epub 2012 May 15.
We use a superoperator representation of the quantum kinetic equation to develop nonequilibrium perturbation theory for an inelastic electron current through a quantum dot. We derive a Lindblad-type kinetic equation for an embedded quantum dot (i.e. a quantum dot connected to Lindblad dissipators through a buffer zone). The kinetic equation is converted to non-Hermitian field theory in Liouville-Fock space. The general nonequilibrium many-body perturbation theory is developed and applied to the quantum dot with electron-vibronic and electron-electron interactions. Our perturbation theory becomes equivalent to a Keldysh nonequilibrium Green's function perturbative treatment provided that the buffer zone is large enough to alleviate the problems associated with approximations of the Lindblad kinetic equation.
我们使用量子动力学方程的超级算符表示来为通过量子点的非弹性电子电流开发非平衡微扰理论。我们为嵌入式量子点（即通过缓冲区与林德布莱德耗散器相连的量子点）导出了林德布莱德型动力学方程。该动力学方程转换为李奥维尔-福克空间中的非厄米场论。发展了一般的非平衡多体微扰理论，并将其应用于具有电子-声子和电子-电子相互作用的量子点。只要缓冲区足够大以减轻与林德布莱德动力学方程的近似相关的问题，我们的微扰理论就等效于凯尔德什非平衡格林函数微扰处理。
