Superradiance-like Electron Transport through a Quantum Dot

TL;DR

This paper theoretically demonstrates that electron transport through a quantum dot can exhibit superradiance-like behavior due to hyperfine interactions, revealing coherent nuclear spin dynamics in a measurable current peak.

Contribution

It introduces a master equation framework for electron transport in quantum dots that incorporates hyperfine interactions, predicting superradiance-like effects in current.

Findings

Strong current peak observed with polarized nuclear spins

Superradiance-like emission analogous to atomic ensembles

Feasible with realistic experimental parameters

Abstract

We theoretically show that intriguing features of coherent many-body physics can be observed in electron transport through a quantum dot (QD). We first derive a master equation based framework for electron transport in the Coulomb-blockade regime which includes hyperfine (HF) interaction with the nuclear spin ensemble in the QD. This general tool is then used to study the leakage current through a single QD in a transport setting. We find that, for an initially polarized nuclear system, the proposed setup leads to a strong current peak, in close analogy with superradiant emission of photons from atomic ensembles. This effect could be observed with realistic experimental parameters and would provide clear evidence of coherent HF dynamics of nuclear spin ensembles in QDs.