Enhancing the fidelity of stimulated Raman transitions with simple phase shifts

TL;DR

This paper presents a simple phase shift technique in stimulated Raman transitions that significantly improves quantum gate fidelity, reduces leakage, and enhances robustness against errors and dissipation without increasing operation time.

Contribution

The authors introduce a straightforward phase shift method that enhances fidelity and robustness of stimulated Raman transitions, outperforming traditional adiabatic elimination approaches.

Findings

Fidelity of quantum gates is significantly improved.

Leakage to intermediate states is approximately halved.

Method is robust against static errors and dissipation.

Abstract

We demonstrate that in stimulated Raman transitions, introducing one or two simple phase shifts to the control fields significantly enhances the fidelity of state manipulation while simultaneously reducing leakage to the intermediate excited state. Our approach achieves high-fidelity quantum gate operations between the two target states under arbitrary detuning conditions. Notably, the average population in the intermediate excited state is approximately halved, without extending the overall evolution time. Additionally, our method exhibits greater robustness to static amplitude and detuning errors compared to conventional adiabatic elimination techniques, and maintains higher fidelity even in the presence of dissipation.