Wireless energy transfer in a non-Hermitian quantum battery

The extraction of energy is one of fundamental challenges in realizing quantum batteries (QBs). Here, we propose two wireless transfer schemes with parity-time symmetries to efficiently extract the energy stored in non-Hermitian QBs to consumption centers. For linear cases, the transfer energy oscillates periodically in the unbroken symmetry region and grows hyperbolically in the broken region. For nonlinear cases, the transfer energy eventually reach and remain steady-state values arising from the feedback mechanism of the nonlinear saturable gain. Furthermore, we show the significant robustness and the ultrafast response of the wireless transfer schemes to sudden movements around one metre. Our work overcomes energy bottlenecks for wireless transfer schemes in QBs and may provide inspirations for practical applications of QBs.