Cavity-Heisenberg spin chain quantum battery

TL;DR

This paper introduces a cavity-Heisenberg spin chain quantum battery with long-range interactions, demonstrating enhanced charging power and energy storage, and explores the role of entanglement in its performance.

Contribution

The study proposes a novel cavity-Heisenberg spin chain quantum battery with improved power scaling and analyzes entanglement's role in energy storage.

Findings

Quantum advantage scaling exceeds 1.5 in CHS QB

Maximum stored energy exhibits critical phenomena

Entanglement is necessary but not sufficient for higher energy storage

Abstract

We propose a cavity-Heisenberg spin chain (CHS) quantum battery (QB) with the long-range interactions and investigate its charging process. The performance of the CHS QB is substantially improved compared to the Heisenberg spin chain (HS) QB. When the number of spins $N \gg 1$, the quantum advantage $\alpha$ of the QB's maximum charging power can be obtained, which approximately satisfies a superlinear scaling relation $P_{max} \propto N^{\alpha}$. For the CHS QB, $\alpha$ can reach and even exceed $1.5$, while the HS QB can only reach about $\alpha=0.75$. We find that the maximum stored energy of the CHS QB has a critical phenomenon. By analyzing the Wigner function, von Neumann entropy, and logarithmic negativity, we demonstrate that entanglement can be a necessary ingredient for QB to store more energy, but not sufficient.