Charger-mediated energy transfer in exactly-solvable models for quantum batteries

TL;DR

This paper systematically analyzes quantum battery models involving two-level systems and oscillators, focusing on energy transfer processes, figures of merit, and the role of non-conserving coupling Hamiltonians.

Contribution

It provides a classification and detailed analysis of quantum battery models, highlighting the effects of different coupling Hamiltonians on energy transfer efficiency.

Findings

Coupling Hamiltonians that do not conserve local excitations significantly impact energy transfer.

The study clarifies the role of various coupling types in charging dynamics.

Optimal charging times depend on the nature of the coupling Hamiltonian.

Abstract

We present a systematic analysis and classification of several models of quantum batteries involving different combinations of two level systems and quantum harmonic oscillators. In particular, we study energy transfer processes from a given quantum system, termed charger, to another one, i.e. the proper battery. In this setting, we analyze different figures of merit, including the charging time, the maximum energy transfer, and the average charging power. The role of coupling Hamiltonians which do not preserve the number of local excitations in the charger-battery system is clarified by properly accounting them in the global energy balance of the model.