Spin current through an ESR quantum dot: A real-time study

TL;DR

This study investigates real-time spin current transport through an ESR quantum dot using advanced simulation techniques, revealing the effects of correlations and dynamics in non-equilibrium conditions.

Contribution

It provides the first detailed real-time analysis of spin transport in a strongly interacting quantum dot under ESR conditions, comparing exact and approximate methods.

Findings

Correlation effects are well captured by Hartree-Fock at quasi-steady state.

HFA misses key features in the real-time dynamics.

Results enhance understanding of ultra-fast spin transport processes.

Abstract

The spin transport in a strongly interacting spin-pump nano-device is studied using the time-dependent variational-matrix-product-state (VMPS) approach. The precession magnetic field generates a dissipationless spin current through the quantum dot. We compute the real time spin current away from the equilibrium condition. Both transient and stationary states are reached in the simulation. The essentially exact results are compared with those from the Hartree-Fock approximation (HFA). It is found that correlation effect on the physical quantities at quasi-steady state are captured well by the HFA for small interaction strength. However the HFA misses many features in the real time dynamics. Results reported here may shed light on the understanding of the ultra-fast processes as well as the interplay of the non-equilibrium and strongly correlated effect in the transport properties.