2011/05/26 by Guy Cohen, Eran Rabani · 1 citation
Engineering · Physics and Astronomy · #Advancements in Semiconductor Devices and Circuit Design #Molecular Junctions and Nanostructures #Quantum and electron transport phenomena #cond-mat.mes-hall #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.84.075150
4 pages, 3 figures
arxiv created 2011/05/26 · openalex publication_date 2011/08/12 · arxiv updated 2013/01/28 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Memory effects play a key role in the dynamics of strongly correlated systems driven out of equilibrium. In this paper, we explore the nature of memory in the nonequilibrium Anderson impurity model. The Nakajima-Zwanzig-Mori formalism is used to derive an exact generalized quantum master equation for the reduced density matrix of the interacting quantum dot, which includes a non-Markovian memory kernel. A real-time path integral formulation is developed in which all diagrams are stochastically sampled in order to numerically evaluate the memory kernel. We explore the effects of temperature down to the Kondo regime, as well as the role of source-drain-bias voltage and bandwidth on the memory. Typically, the memory decays on time scales significantly shorter than the dynamics of the reduced density matrix itself, yet under certain conditions, it develops a low magnitude but long-ranged tail. In addition, we address the conditions required for the existence, uniqueness, and stability of a steady state.