Tunneling spectroscopy of spin-selective Aharonov-Bohm oscillations in a lateral triple quantum dot molecule

TL;DR

This paper develops a theoretical framework for tunneling spectroscopy in a triple quantum dot system, revealing spin-selective Aharonov-Bohm oscillations and negative differential conductance due to spectral weight redistribution.

Contribution

It introduces a combined exact many-body and rate equation approach to analyze spin-dependent interference effects in quantum dot molecules.

Findings

Prediction of negative differential conductance due to spectral redistribution.

Identification of spin-selective Aharonov-Bohm oscillations in hole states.

Analysis of interference effects on singlet and triplet states in magnetic fields.

Abstract

We present a theory of tunneling spectroscopy of spin-selective Aharonov-Bohm oscillations in a lateral triple quantum dot molecule. The theory combines exact treatment of an isolated many-body system with the rate equation approach when the quantum dot molecule is weakly connected to the leads subject to arbitrary source-drain bias. The tunneling spectroscopy of the many-body complex is analyzed using the spectral functions of the system and applied to holes in a quantum dot molecule. Negative differential conductance is predicted and explained as a result of the redistribution of the spectral weight between transport channels. It is shown that different interference effects on singlet and triplet hole states in a magnetic field lead to spin-selective Aharonov-Bohm oscillations.