Nonreciprocal multifunctional electromagnetic wave controller

Abstract We proposed a promising method to achieve phase modulation utilizing photonic crystal (PC). The broken parity and time-reversal symmetries induce intrinsic nonreciprocity. The supported one-way phase velocity which has a close relationship with biased magnetic field (BMF). Different from the most metasurfaces, only one structure is required to realize electromagnetic wave spatial distributions by adjusting each cell’s BMF. As an application, a deflector with only one column shows obviously nonreciprocity accompanied with magnetically tunable deflection angle. We further designed a flat lens and an axicon under different applied BMF distributions. Such phase modulation by PC provides a new flexible way to realize phase modulation, which can reduce difficulties in design and fabrication.