Quantum manipulation of two-electron spin states in metastable double quantum dots

TL;DR

This paper experimentally investigates the control of two-electron spin states in metastable double quantum dots, demonstrating enhanced coherence and coupling capabilities that could advance quantum computing technologies.

Contribution

It introduces the use of metastable double quantum dots for improved coherent coupling of electron spins, surpassing conventional double dot control.

Findings

Higher control levels in metastable double dots compared to conventional ones

Successful coherent coupling of two electron spins following Loss and DiVincenzo's scheme

Potential for increasing the number of coherently coupled quantum dots

Abstract

We studied experimentally the dynamics of the exchange interaction between two antiparallel electron spins in a so-called metastable double quantum dot where coupling to the electron reservoirs can be ignored. We demonstrate that the level of control of such a double dot is higher than in conventional double dots. In particular, it allows to couple coherently two electron spins in an efficient manner following a scheme initially proposed by Loss and DiVincenzo. The present study demonstrates that metastable quantum dots are a possible route to increase the number of coherently coupled quantum dots.