Gate control of Berry phase in III-V semiconductor quantum dots

TL;DR

This paper explores how the Berry phase in III-V semiconductor quantum dots can be controlled via electric fields and spin-orbit interactions, with implications for topological quantum computing.

Contribution

It demonstrates gate-controlled manipulation of Berry phase in quantum dots through spin-orbit coupling interplay and electric fields, advancing quantum computing potential.

Findings

Berry phase is highly sensitive to Rashba and Dresselhaus spin-orbit couplings.

Berry phase can be induced from quantum states differing by one quantum number.

Sign change in g-factor affects the Berry phase.

Abstract

Berry phase in semiconductor quantum dots (QDs) can be induced by moving the dots adiabatically in a closed loop with the application of the distortion potential in the lateral direction. We show that the Berry phase is highly sensitive to the electric fields arising from the interplay between the Rashba and the Dresselhaus spin-orbit couplings. We report that the accumulated Berry phase can be induced from other available quantum state that are only differed by one quantum number of the same spin state. The sign change in the g-factor due to the penetration of the Bloch wavefunctions into the barrier material can be reflected in the Berry phase. We solve the time dependent Schr$\mathrm{\ddot{o}}$dinger equation and investigate the evolution of the spin dynamics during the adiabatic movement of the QDs in the 2D plane. Our results might open the possibilities of building a topological quantum dot quantum computer where the Berry phase can be engineered and can be manipulated with the application of the spin-orbit couplings through gate controlled electric fields.