Reconfigurable Electromagnetic Diode and Limiter via Digital Nonlinear Metasurface

Electromagnetic (EM) diode and limiter are two typical nonlinear devices based on metasurface configurations, yet with transmission rate dependent on the incident microwave in an opposite way. Under the passive architecture of nonlinear metamaterial, it is difficult to have these two functions integrated into a shared hardware. In this paper, we present a novel metasurface based on a digital nonlinear mechanism, by which the above two functions are integrated and can be triggered as demanded. The metasurface consists of a tunable transmissive surface and digital module. A prototype is measured under microwave illuminations with varying intensities from forward and backward directions, and the unidirectional diode and limiter properties are well demonstrated.