Controlling inelastic cotunneling through an interacting quantum dot by a circularly-polarized field

TL;DR

This paper investigates how a circularly-polarized magnetic field can control inelastic cotunneling in a Coulomb-blockaded quantum dot, revealing a transition in conductance related to photon-assisted spin-flip processes.

Contribution

It introduces a quantum Langevin equation approach to analyze controllable cotunneling in quantum dots under combined magnetic fields, highlighting a novel conductance transition.

Findings

Predicted a splitting-zero-anomaly-splitting transition in differential conductance.

Identified photon-assisted spin-flip cotunneling as the key mechanism.

Demonstrated controllability of cotunneling current via magnetic field frequency.

Abstract

We study inelastic cotunneling through a strong Coulomb-blockaded quantum dot subject to a static magnetic field and a perpendicular circularly-polarized magnetic field using a quantum Langevin equation approach. Our calculation predicts an interesting controllable cotunneling current characteristic, splitting--zero-anomaly--splitting transition of the differential conductance with increasing the driving frequency, ascribing to the role of {\em photon-assisted spin-flip} cotunneling processes.