Harnessing Nth Root Gates for Energy Storage

TL;DR

This paper investigates the use of Nth-root quantum gates in thermodynamic protocols to enhance quantum battery charging efficiency, analyzing small circuits and optimizing initial conditions for improved performance.

Contribution

It introduces fractional control-not gates into quantum thermodynamics, demonstrating their application in quantum battery protocols and optimizing initial parameters for better energy storage.

Findings

Nth-root gates enable paced two-qubit operations.

Optimized initial coherence improves battery performance.

Feasibility discussed for experimental implementation.

Abstract

We explore the use of fractional control-not gates in quantum thermodynamics. The Nth-root gate allows for a paced application of two-qubit operations. We apply it in quantum thermodynamic protocols for charging a quantum battery. Circuits for three (and two) qubits are analysed by considering the generated ergotropy and other measures of performance. We also perform an optimisation of initial system parameters, e.g. initial quantum coherence of one of the qubits affects strongly the efficiency of protocols and the system's performance as a battery. Finally, we briefly discuss the feasibility for an experimental realisation.