Detection of Geometric Phases in Flux Qubits with Coherent Pulses

TL;DR

This paper presents a practical method to detect geometric (Berry) phases in flux qubits using detuned microwave pulses, enabling high-resolution readouts and phase gate implementation via inductance coupling.

Contribution

It introduces an experimentally feasible scheme to measure geometric phases in flux qubits through microwave pulse techniques and demonstrates how to implement phase gates based on these phases.

Findings

Detection of Berry phase via persistent current measurement

Optimal pulse amplitude for high readout resolution

Implementation of controlled phase shift gates using geometric phases

Abstract

We propose a experimentally feasible scheme to demonstrate the geometric phase in flux qubits by means of detuning coherent microwave pulse techniques. Through measuring the probability of the persistent current state in flux qubits, one can detect the Berry phase that is acquired with system's Hamiltonian adiabatical circular evolution in the parameter space. Furthermore, we show that one should choose an appropriate amplitude of pulses in an experiment to obtain high readout resolution when detuning frequency of pulses is fixed and controlled phase shift gates can be implemented based on the geometric phases by inductance coupling two flux qubits.