Adiabatic Control of the Electron Phase in a Quantum Dot

TL;DR

This paper proposes a method to control and detect the electron phase in a quantum dot using adiabatic modulation of electric fields near degeneracy points, with potential applications in quantum information processing.

Contribution

It introduces a novel approach to manipulate and measure Berry phases in quantum dots through adiabatic electric field control and interferometric detection.

Findings

Theoretical framework for phase control via electric field modulation.

Design of a capacitively coupled interferometric detection scheme.

Analysis of the effective Hamiltonian for phase-sensitive interactions.

Abstract

A Berry phase can be added to the wavefunction of an isolated quantum dot by adiabatically modulating a nonuniform electric field along a time-cycle. The dot is tuned close to a three-level degeneracy, which provides a wide range of possibilities of control. We propose to detect the accumulated phase by capacitively coupling the dot to a double-path inteferometer. The effective Hamiltonian for the phase-sensitive coupling is discussed in detail.