Oscillatory spin relaxation rates in quantum dots

TL;DR

This paper investigates how phonon interactions, magnetic fields, and quantum dot size influence spin relaxation times, revealing conditions for extremely long relaxation times and aligning with experimental data.

Contribution

It provides a detailed analysis of phonon-induced spin relaxation in quantum dots considering various material and field parameters, highlighting conditions for prolonged spin coherence.

Findings

Spin relaxation times can reach seconds under certain confinements.

Magnetic field and dot size significantly affect relaxation rates.

Results agree with experimental data in GaAs quantum dots.

Abstract

Phonon-induced spin relaxation rates in quantum dots are studied as function of in-plane and perpendicular magnetic fields, temperature and electric field, for different dot sizes. We consider Rashba and Dresselhaus spin-orbit mixing in diferent materials, and show how Zeeman sublevels can relax via piezoelectric and deformation potential coupling to acoustic phonons. We find that strong lateral and vertical confinements may induce minima in the rates at particular values of the magnetic field, where spin relaxation times can reach even seconds. We obtain good agreement with experimental findings in GaAs quantum dots.