Spin relaxation in an InAs quantum dot in the presence of terahertz driving fields

TL;DR

This paper investigates how terahertz magnetic fields influence spin relaxation times in InAs quantum dots with Rashba spin-orbit coupling, revealing controllable prolongation or shortening of relaxation times via sideband-modulated spin-phonon interactions.

Contribution

It develops a generalized Floquet-Markov theoretical framework to analyze spin relaxation under strong terahertz driving fields in quantum dots with spin-orbit coupling.

Findings

Terahertz magnetic fields can either prolong or shorten spin relaxation times.

Spin-phonon scattering is modulated by sidebands due to the terahertz field.

The manipulation of spin relaxation offers potential for quantum information applications.

Abstract

The spin relaxation in a 1D InAs quantum dot with the Rashba spin-orbit coupling under driving THz magnetic fields is investigated by developing the kinetic equation with the help of the Floquet-Markov theory, which is generalized to the system with the spin-orbit coupling, to include both the strong driving field and the electron-phonon scattering. The spin relaxation time can be effectively prolonged or shortened by the terahertz magnetic field depending on the frequency and strength of the terahertz magnetic field. The effect can be understood as the sideband-modulated spin-phonon scattering. This offers an additional way to manipulate the spin relaxation time.