Transient probing of the symmetry and the asymmetry of electron interference

TL;DR

This paper investigates how initial states influence transient electron transport symmetries in a quantum dot interferometer, revealing flux-dependent symmetry relations in transient currents.

Contribution

It explicitly analyzes the interplay between initial state symmetries and system structure during transient electron transport in a quantum dot system.

Findings

Symmetry relations between transient in-tunneling and out-tunneling for certain initial states.

Flux-even and flux-odd current components exhibit distinct symmetry relations.

Transient current behaviors depend on initial occupations and system symmetries.

Abstract

The transient processes of electron transport in nano-scale devices exhibit special phenomena that exist only in the transient regime. Besides how fast the steady states are approached, one interesting aspect of transient transport arises from its strong dependence on the initial state of the system. Here we address the issue of how the symmetries embedded in the initial state interplay with those of the system structure in the course of transient transports. We explicitly explore the transient currents arising from various initial occupations in a double-quantum-dot Aharonov-Bohm interferometer. We find symmetry relations between the transient in-tunneling and out-tunneling dynamics for initially empty or full quantum dots when the energy levels in the electrodes are symmetrically distributed with respect to the energy levels in the QDs. This is true for whatever applied fluxes. We also find the flux-even components of the currents and the flux-odd components of the currents exhibit distinct cross-lead symmetric relations.