Voltage-Controlled Berry Phases in Two Coupled Quantum Dots

TL;DR

This paper theoretically explores how voltage control can dramatically alter Berry phases in coupled quantum dots, enabling potential applications in quantum computation through geometric phase manipulation.

Contribution

It introduces a method to control Berry phases in coupled quantum dots using voltage, highlighting a new approach for quantum computation based on geometric phases.

Findings

Berry phases can be switched from 0 to 2π by voltage control.

Berry phases are significantly affected by tunneling variations.

The scheme is feasible for quantum computation applications.

Abstract

The voltage-controlled Berry phases in two vertically coupled InGaAs/GaAs quantum dots are investigated theoretically. It is found that Berry phases can be changed dramatically from 0 to 2$\pi$ (or 2$\pi$ to 0) only simply by turning the external voltage. Under realistic conditions, as the tunneling is varied from $0.8eV$ to $0.9eV$ via a bias voltage, the Berry phases are altered obviously, which can be detected in an interference experiment. The scheme is expected to be useful in constructing quantum computation based on geometric phases in an asymmetrical double quantum dot controlled by voltage.