Improving quantum gate fidelities using optimized Euler angles

TL;DR

This paper presents an algorithm for optimizing Euler angles to enhance quantum gate fidelities, enabling efficient single-qubit gate implementation under control restrictions without increasing operation times.

Contribution

The authors introduce a novel algorithm for calculating optimized Euler angles that improve quantum gate fidelity even with limited control Hamiltonians.

Findings

Optimized Euler angles significantly improve quantum gate fidelity.

The scheme is effective even with nearly orthogonal Hamiltonians.

It does not increase local operations or gate times.

Abstract

An explicit algorithm for calculating the optimized Euler angles for both qubit state transfer and gate engineering given two arbitary fixed Hamiltonians is presented. It is shown how the algorithm enables us to efficiently implement single qubit gates even if the control is severely restricted and the experimentally accessible Hamiltonians are far from orthogonal. It is further shown that using the optimized Euler angles can significantly improve the fidelity of quantum operations even for systems where the experimentally accessible Hamiltonians are nearly orthogonal. Unlike schemes such as composite pulses, the proposed scheme does not significantly increase the number of local operations or gate operation times.