Optical nonreciprocity via transmissive time-modulated metasurfaces

Abstract The frequency mixing property of time-modulated metasurfaces, attributed to the well-known phenomenon temporal photonic transition, has led several exotic functionalities in last lustrum. Based on this concept, we demonstrate possibility achieving nonreciprocal responses near-infrared regime via combining a platform and static high-Q metasurface. In particular, metasurface is designed up-convert incident tone first higher-order harmonic, while implemented establish filtering behavior with respect frequency. It shown that receiver port acquires transmitted signal forward direction, amount received power becomes negligible under time-reversal scenario, which indicates presented configuration exhibits different optical from opposite directions. addition, role operating wavelength modulation isolation level are investigated, it demonstrated by appropriate selection, can reach ?30 dB. Since time response obtained pure modulation, believe idea paper be utmost importance various applications, such as tunable isolators.