Quantum Charging Advantage in Superconducting Solid-State Batteries

TL;DR

This paper demonstrates experimentally that superconducting quantum batteries can achieve quantum charging advantage (QCA) using scalable, nearest-neighbor interactions in a superconducting processor, surpassing classical charging performance.

Contribution

It provides the first experimental demonstration of scalable quantum charging advantage in a superconducting solid-state battery with up to 12 cells using standard methods.

Findings

Quantum charging advantage observed in superconducting qubits.

Effective implementation with 2 to 12 battery cells.

Quantum features confirmed through measurements of ergotropy and entanglement.

Abstract

Quantum battery, as a novel energy storage device, offers the potential for unprecedented efficiency and performance beyond the capabilities of classical systems, with broad implications for future quantum technologies. Here, we experimentally \RefC{demonstrate quantum charging advantage (QCA)} in a scalable solid-state quantum battery. More specifically, we show how double-excitation Hamiltonians for two-level systems promote scalable QCA \RefB{with standard methods.} We effectively implement the collective evolution of quantum systems with 2 up to 12 battery cells in a superconducting quantum processor, and study the performance of quantum charging compared to its uncorrelated classical counterpart. The model considered is a linear chain of superconducting transmon qubits with only \textit{nearest-neighbor} and \textit{pairwise} interactions, which constitute the simplest model of a multi-cell quantum battery. Our results empirically realize substantial QCA without the necessity of adopting long-range and many-body interactions \RefB{ and showcase the quantum features of the QB charging processes with measurements of non-zero coherent ergotropy, incoherent ergotropy and entanglement,} revealing a promising prospect for further developments of efficient and experimentally feasible protocols for QCA.