Charging Dicke and Tavis--Cummings quantum batteries with a š¯’«š¯’Æ-symmetric lossy--gain cavity pair
Abstract
We study how a parity--time-symmetric photonic environment changes the charging of Dicke and Tavis--Cummings quantum batteries. For atoms prepared in the collective ground state the excitation number grows as the square of the charging time, with a coefficient set by the initial mean photon number; the counter-rotating terms of the Dicke model add one to four times that number. Conservation of the total excitation number turns this into an exact ceiling on the stored Tavis--Cummings energy, the transition energy times the smaller of the photon and atom numbers, met numerically to within two per cent, which the Dicke terms overshoot by a few per cent at ultrastrong coupling. We then couple a battery to a lossy--gain pair, keeping the parity--time symmetry intact by putting an identical battery in each cavity; the closed moment system puts the exceptional point at the loss rate. Below it the gain cavity fills and the gain-side battery charges while the lossy-side one stays empty; above it photons are shuttled away and dissipated. Solving the full Lindblad equation with batched Monte--Carlo wave functions, we find that the gain-side battery gains thirty-nine, twenty-six and twenty-eight per cent in stored energy, power and ergotropy in the broken phase and loses sixty-five, thirty-five and sixty-five per cent deep in the unbroken phase, where the lossy-side battery overtakes it. Restoring the counter-rotating terms leaves all of this unchanged within the statistical error; what they add is a reactive oscillation at twice the transition frequency that does no net work but nearly doubles the peak of the instantaneous power. The extra energy is of lower quality, the recoverable fraction dropping from about ninety-eight to ninety per cent. The optimum sits on the broken side, close to but not at the exceptional point.
Related
- Charging Quantum Batteries with Chiral Squeezing
- Fast charging of quantum batteries assisted by nonlinear couplings
- Enhanced charging in open Rabi and Dicke quantum batteries
- Quantum Optics of harmonic generation in the strongly driven Jaynes-Cummings-type system
- Dynamical protection of quantum steering and fidelity dynamics in the double Jaynes-Cummings model
BibTeX
@misc{tang2026charging,
title = {{Charging Dicke and Tavis--Cummings quantum batteries with a $\mathcalPT$-symmetric lossy--gain cavity pair}},
author = {Shiqing Tang and Qing Yu and Ying Li and Cuilu Zhai and Zhao-Hui Peng and Wangjun Lu},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.07921},
eprint = {2610.07921},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.07921},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Charging Dicke and Tavis--Cummings quantum batteries with a š¯’«š¯’Æ-symmetric lossy--gain cavity pair
AU - Shiqing Tang
AU - Qing Yu
AU - Ying Li
AU - Cuilu Zhai
AU - Zhao-Hui Peng
AU - Wangjun Lu
PY - 2026
DA - 2026/10/06
PB - arXiv
DO - 10.48550/arxiv.2610.07921
UR - https://arxiv.org/abs/2610.07921
AB - We study how a parity--time-symmetric photonic environment changes the charging of Dicke and Tavis--Cummings quantum batteries. For atoms prepared in the collective ground state the excitation number grows as the square of the charging time, with a coefficient set by the initial mean photon number; the counter-rotating terms of the Dicke model add one to four times that number. Conservation of the total excitation number turns this into an exact ceiling on the stored Tavis--Cummings energy, the transition energy times the smaller of the photon and atom numbers, met numerically to within two per cent, which the Dicke terms overshoot by a few per cent at ultrastrong coupling. We then couple a battery to a lossy--gain pair, keeping the parity--time symmetry intact by putting an identical battery in each cavity; the closed moment system puts the exceptional point at the loss rate. Below it the gain cavity fills and the gain-side battery charges while the lossy-side one stays empty; above it photons are shuttled away and dissipated. Solving the full Lindblad equation with batched Monte--Carlo wave functions, we find that the gain-side battery gains thirty-nine, twenty-six and twenty-eight per cent in stored energy, power and ergotropy in the broken phase and loses sixty-five, thirty-five and sixty-five per cent deep in the unbroken phase, where the lossy-side battery overtakes it. Restoring the counter-rotating terms leaves all of this unchanged within the statistical error; what they add is a reactive oscillation at twice the transition frequency that does no net work but nearly doubles the peak of the instantaneous power. The extra energy is of lower quality, the recoverable fraction dropping from about ninety-eight to ninety per cent. The optimum sits on the broken side, close to but not at the exceptional point.
ER -