Shortcut to adiabaticity improvement of STIRAP based qubit rotation

TL;DR

This paper enhances the speed and fidelity of qubit rotations in quantum computing by applying shortcut to adiabaticity methods to the STIRAP scheme, enabling faster, more reliable quantum logic gates.

Contribution

It introduces a novel application of shortcut to adiabaticity techniques to improve STIRAP-based qubit rotations in quantum control.

Findings

Improved fidelity of qubit rotations in the diabatic regime.

Implementation via direct and effective connections in multi-level systems.

Enhanced quantum gate performance with modified pulse schemes.

Abstract

Robust quantum control is essential for the development of quantum computers, which rely on precise manipulation of qubits. One form of quantum control is stimulated Raman adiabatic passage (STIRAP), which ordinarily is a state transfer protocol but was extended by Kis and Renzoni (Phys. Rev. A 65, 032318 (2002)) to perform qubit rotations. Shortcut methods to adiabaticity for STIRAP have been shown to speed up adiabatic processes, beyond the adiabatic criterion, with high fidelity. Here, we apply shortcut to adiabaticity methods to the STIRAP qubit rotation scheme to improve the performance of quantum logic gates. The scheme can be implemented via direct connections between ground states in a 4-level $\Lambda$ system or effective connections in a 5-level $\Lambda$ system with modified pulses that implement transitionless quantum driving via the addition of a counterdiabatic driving term. We show that the extended shortcut to adiabaticity method serves to improve the fidelity of qubit rotations in the diabatic regime.