Saturable nonlinearities in a driven-dissipative bosonic quantum battery

TL;DR

This paper explores how saturable nonlinearities in a driven-dissipative bosonic quantum battery influence energy storage and extraction, revealing that such nonlinearities can enhance maximum energy and allow tuning of work extraction.

Contribution

It introduces the impact of saturable nonlinearities on the energy spectrum and charging dynamics of bosonic quantum batteries, a novel aspect compared to Kerr-type nonlinearities.

Findings

Saturable nonlinearity leads to a bounded and nonlinear energy spectrum.

Nonlinear spectral structure affects transient and steady-state energy and ergotropy.

Saturable nonlinearity can enhance maximum stored energy and enable control over work extraction.

Abstract

We investigate the charging of a nonlinear quantum battery consisting of a single bosonic mode subject to a saturable nonlinearity, coherent driving, and dissipation. In contrast to Kerr-type anharmonicities, the saturable interaction induces a bounded and nonlinear distortion of the energy spectrum, leading to a progressive increase in the density of energy levels. We analyze the time evolution of the energy and ergotropy of the battery by solving a Lindblad master equation and show that the nonlinear spectral structure significantly affects both transient charging behavior and steady-state properties. Our results reveal that, for a broad range of parameters, the saturable nonlinearity enhances the maximum stored energy and modifies the ergotropy generation in the presence of losses. The interplay between dissipation and bounded spectral nonlinearity provides a controllable mechanism to tune energy storage and work extraction in bosonic quantum batteries.