Aharonov-Bohm phase operations on a double-barrier nanoring charge qubit

TL;DR

This paper proposes a charge qubit scheme using a double-barrier nanoring where quantum gates are implemented via Aharonov-Bohm phase manipulation with magnetic flux and electric fields, emphasizing smooth control to prevent errors.

Contribution

It introduces a novel charge qubit implementation in a nanoring utilizing Aharonov-Bohm phase for gate operations, avoiding the need for tunable tunnelings.

Findings

The qubit states are encoded in the spatial wavefunctions of the nanoring.

Magnetic flux and electric fields can effectively implement quantum gates.

Smooth switching of external fields is crucial to minimize errors.

Abstract

We present a scheme for charge qubit implementation in a double-barrier nanoring. The logical states of the qubit are encoded in the spatial wavefunctions of the two lowest energy states of the system. The Aharonov-Bohm phase introduced by magnetic flux, instead of tunable tunnelings, along with electric fields can be used for implementing the quantum gate operations. During the operations, the external fields should be switched smoothly enough to avoid the errors caused by the transition to higher-lying states. The structure and field effects on the validity of the qubit are also studied.