Non-perturbative Theory of Pauli Spin Blockade

TL;DR

This paper develops a non-perturbative theoretical framework using the hierarchical equations of motion to analyze Pauli spin blockade in double quantum dots, providing detailed physical insights and aligning with experimental observations.

Contribution

It introduces a systematic non-perturbative approach to study PSB in DQDs considering electron interactions, enhancing understanding of gate control and exchange effects.

Findings

PSB effect can be explicitly elucidated and manipulated via gate voltages.

Strong antiferromagnetic exchange coupling can lift the PSB.

Theoretical results are consistent with experimental measurements.

Abstract

Pauli spin blockade (PSB) is a significant physical effect in double quantum dot (DQD) systems. In this paper, we start from the fundamental quantum model of the DQD with the electron-electron interaction being considered, and then systematically study the PSB effect in DQD by using a recently developed non-perturbative method, the hierarchical equations of motion (HEOM) approach. The physical picture of the PSB is elucidated explicitly and the gate voltage manipulation is described minutely, which are both qualitatively consistent with the experimental measurements. When dotdot exchange interaction is involved, the PSB effect may be lifted by the strong antiferromagnetic exchange coupling.