2013/01/31 by Martin Nuss, M. C. Nuss, Martin Ganahl +3 · 15 citations
Chemistry · Physics and Astronomy · #Biasing #Chemistry #Condensed matter physics #Entropy production #Fermion #Non-equilibrium thermodynamics #Observable #Physics #Physics of Superconductivity and Magnetism #Quantum #Quantum and electron transport phenomena #Quantum dot #Quantum electrodynamics #Quantum entanglement #Quantum many-body systems #Quantum mechanics #Statistical physics #Steady state (chemistry) #Time evolution #Voltage #cond-mat.mes-hall #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.88.045132
published in Physical Review B 88(4) (American Physical Society) · 15 pages, 11 figures
openalex publication_date 2013/07/29 · arxiv created 2013/07/30 · arxiv updated 2013/07/31 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
We study the time evolution and steady state of the charge current in a single-impurity Anderson model, using matrix product states techniques. A nonequilibrium situation is imposed by applying a bias voltage across one-dimensional tight-binding leads. Focusing on particle-hole symmetry, we extract current-voltage characteristics from universal low-bias up to high-bias regimes, where band effects start to play a dominant role. We discuss three quenches, which after strongly quench-dependent transients yield the same steady-state current. Among these quenches we identify those favorable for extracting steady-state observables. The period of short-time oscillations is shown to compare well to real-time renormalization group results for a simpler model of spinless fermions. We find indications that many-body effects play an important role at high-bias voltage and finite bandwidth of the metallic leads. The growth of entanglement entropy after a certain time scale \ensuremath∝\ensuremathΔ^\ensuremath-1 is the major limiting factor for calculating the time evolution. We show that the magnitude of the steady-state current positively correlates with entanglement entropy. The role of high-energy states for the steady-state current is explored by considering a damping term in the time evolution.