Green's functions from real-time bold-line Monte Carlo calculations: spectral properties of the nonequilibrium Anderson impurity model.
The nonequilibrium spectral properties of the Anderson impurity model with a chemical potential bias are investigated within a numerically exact real-time quantum Monte Carlo formalism. The two-time correlation function is computed in a form suitable for nonequilibrium dynamical mean field calculations. Additionally, the evolution of the model's spectral properties are simulated in an alternative representation, defined by a hypothetical but experimentally realizable weakly coupled auxiliary lead. The voltage splitting of the Kondo peak is confirmed and the dynamics of its formation after a coupling or gate quench are studied. This representation is shown to contain additional information about the dot's population dynamics. Further, we show that the voltage-dependent differential conductance gives a reasonable qualitative estimate of the equilibrium spectral function, but significant qualitative differences are found including incorrect trends and spurious temperature dependent effects.
Department of Chemistry, Columbia University, New York, New York 10027, USA and Department of Physics, Columbia University, New York, New York 10027, USA.
Guy
G
Cohen
Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, USA.
Emanuel
E
Gull
Department of Chemistry, Columbia University, New York, New York 10027, USA.
David R
DR
Reichman
Department of Physics, Columbia University, New York, New York 10027, USA.
Andrew J
AJ
Millis