A universal non-Hermitian platform for bound state in the continuum enhanced wireless power transfer

Non-Hermitian systems with parity–time(PT)-symmetry have been extensively studied and rapidly developed in resonance wireless power transfer(WPT).The WPT system that satisfies PT-symmetry always has real eigenvalues,which promote efficient energy transfer.However,meeting the condition of PT-symmetry is one of the most puzzling issues.Stable power transfer under different transmission conditions is also a great challenge.Bound state in the continuum(BIC)supporting extreme quality-factor mode provides an opportunity for efficient WPT.Here,we propose theoretically and demonstrate experimentally that BIC widely exists in resonance-coupled systems without PT-symmetry,and it can even realize more stable and efficient power transfer than PT-symmetric systems.Importantly,BIC for efficient WPT is universal and suitable in standard second-order and even high-order WPT systems.Our results not only extend non-Hermitian physics beyond PT-symmetry,but also bridge the gap between BIC and practical application engineering,such as highperformance WPT,wireless sensing and communications.