Quantum Dynamics of Electron-Nuclei Coupled System in a Double Quantum Dot

TL;DR

This paper investigates how hyperfine interactions in double quantum dots influence electron spin dynamics, demonstrating measurement-induced nuclear spin purification, extended coherence times, and implications for quantum information processing.

Contribution

It introduces a method to extend electron spin coherence via conditional measurements and explores nuclear spin purification in coupled quantum dot systems.

Findings

Successive measurements cause electron spin bunching due to nuclear correlations.

Conditional measurements can purify nuclear spins, leading to electron spin revivals.

Electron spin coherence time is extended through measurement-based nuclear spin control.

Abstract

Hyperfine interaction of electron spins with nuclear spins, in coupled double quantum dots is studied. Results of successive electron spin measurements exhibit bunching due to correlations induced via the nuclear spins. Further nuclear spins can be purified via conditional electron spin measurements which lead to electron spin revivals in the conditional probabilities. The electron spin coherence time can be extended via conditional measurements. The results are extended to a single electron on a single QD.