2008/11/05 by Peter Fritsch, Stefan Kehrein · 18 citations
Engineering · Physics and Astronomy · #Advancements in Semiconductor Devices and Circuit Design #Hamiltonian (control theory) #Impurity #Kondo effect #Kondo model #Logarithm #Non-equilibrium thermodynamics #Physics #Physics of Superconductivity and Magnetism #Quantum #Quantum and electron transport phenomena #Quantum decoherence #Quantum electrodynamics #Quantum mechanics #Scaling #Statistical physics #Unitary state #cond-mat.str-el
paper · pdf · doi:10.1016/j.aop.2009.01.004
published in Annals of Physics 324(5), 1105-1135 (Elsevier BV) · 22 pages, 15 figures
arxiv created 2008/11/05 · openalex publication_date 2009/02/13 · arxiv updated 2010/03/22 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The quintessential description of Kondo physics in equilibrium is obtained within a scaling picture that shows the buildup of Kondo screening at low temperature. For the non-equilibrium Kondo model with a voltage bias the key new feature are decoherence effects due to the current across the impurity. In the present paper we show how one can develop a consistent framework for studying the non-equilibrium Kondo model within a scaling picture of infinitesimal unitary transformations (flow equations). Decoherence effects appear naturally in third order of the beta-function and dominate the Hamiltonian flow for sufficiently large voltage bias. We work out the spin dynamics in non-equilibrium and compare it with finite temperature equilibrium results. In particular, we report on the behavior of the static spin susceptibility including leading logarithmic corrections and compare it with the celebrated equilibrium result as a function of temperature.