Realization of nonreciprocal transmission with low insertion loss and high contrast simultaneously is in great demand for one-way optical communication and information processing. Here we propose a generic approach to achieving perfect nonreciprocity that allows lossless unidirectional transmission by engineering energy losses. The loss of the intermediate mode induces a phase lag impinging on the indirect channel for energy transmission, which does not depend on the energy transmission direction. When the direct transmission channel coexists with the indirect lossy transmission channel, the dual-channel interference can be tuned to be destructive simultaneously for backward transmission from the rightmost mode to the leftmost mode, and for forward transmission from the leftmost mode to the intermediate mode. The former interference outcome corresponds to 100% nonreciprocity contrast, and the latter guarantees zero insertion loss for forward transmission. Additionally, our scheme also allows a nonreciprocity response over a wide bandwidth by increasing the losses while keeping perfect nonreciprocity at resonance. The robustness against loss indicates that our scheme is advantageous in the implementation of nonreciprocal optical devices with high performance.
Floquet engineering of nonreciprocal light-induced dipolar interactions
Vienna Center for Quantum Science and Technology (VCQ), Atominstitut, TU Wien（维也纳量子科学与技术中心，原子研究所，维也纳工业大学）；Vienna Center for Quantum Science and Technology (VCQ), Faculty of Physics, University of Vienna（维也纳量子科学与技术中心，物理学院，维也纳大学）；Institute for Complex Quantum Systems, Ulm University（复杂量子系统研究所，乌尔姆大学）
Soliton Transitions Mediated by Skin-Mode Localization and Band Nonreciprocity
Fudan University（复旦大学）；Institute of Physics, Chinese Academy of Sciences（中国科学院物理研究所）；Kavli Institute for Theoretical Sciences, Chinese Academy of Sciences（中国科学院理论科学卡弗里研究所）
