Failure of mean-field approach in out-of-equilibrium Anderson model

Abstract

To explore the limitations of the mean field approximation, frequently used in \textit{ab initio} molecular electronics calculations, we study an out-of-equilibrium Anderson impurity model in a scattering formalism. We find regions in the parameter space where both magnetic and non-magnetic solutions are stable. We also observe a hysteresis in the non-equilibrium magnetization and current as a function of the applied bias voltage. The mean field method also predicts incorrectly local moment formation for large biases and a spin polarized current, and unphysical kinks appear in various physical quantities. The mean field approximation thus fails in every region where it predicts local moment formation.

5 pages, 5 figures

References in corpus (1)

• Nonequilibrium magnetotransport through a quantum dot: An interpolative perturbative approach

Cited by in corpus (3)

• Iterative real-time path integral approach to nonequilibrium quantum transport
• Magnetotransport in Aharonov Bohm interferometers: Exact numerical simulations
• Bistability in the Tunnelling Current through a Ring of $N$ Coupled Quantum Dots