Many-body localized quantum batteries

The collective and quantum behavior of many-body systems may be harnessed to achieve fast charging of energy storage devices, which have been recently dubbed quantum batteries. In this paper, we present an extensive numerical analysis of energy flow in a quantum battery described by a disordered quantum Ising chain Hamiltonian, whose equilibrium phase diagram presents many-body localized (MBL), Anderson localized (AL), and ergodic phases. We demonstrate that (i) the low amount of entanglement of the MBL phase guarantees much better work extraction capabilities, measured by the ergotropy, than the ergodic phase and (ii) interactions suppress temporal energy fluctuations in comparison with those of the noninteracting AL phase. Finally, we show that the statistical distribution of values of the optimal charging time is a clear-cut diagnostic tool of the MBL phase.