Optimizing Counterdiabaticity by Variational Quantum Circuits

TL;DR

This paper introduces a variational quantum circuit approach to optimize counterdiabatic driving, enhancing quantum state preparation fidelity and outperforming traditional algorithms in bounded time scenarios.

Contribution

It presents a novel variational method to optimize counterdiabatic terms using quantum circuits, improving adiabatic evolution in quantum algorithms.

Findings

Enhanced fidelity in GHZ state preparation.

Outperforms quantum approximate optimization algorithm.

Effective in bounded time quantum evolutions.

Abstract

Utilizing counterdiabatic (CD) driving - aiming at suppression of diabatic transition - in digitized adiabatic evolution have garnered immense interest in quantum protocols and algorithms. However, improving the approximate CD terms with a nested commutator ansatz is a challenging task. In this work, we propose a technique of finding optimal coefficients of the CD terms using a variational quantum circuit. By classical optimizations routines, the parameters of this circuit are optimized to provide the coefficients corresponding to the CD terms. Then their improved performance is exemplified in Greenberger-Horne-Zeilinger state preparation on nearest-neighbor Ising model. Finally, we also show the advantage over the usual quantum approximation optimization algorithm, in terms of fidelity with bounded time.