Graphene reflectarray that steers vortex THz waves

A graphene reflectarray is designed to realize two functions simultaneously at terahertz frequency: generating vortex waves, and steering the waves. Four parts of graphene patches with different values of reflection phase are used to generate vortex waves. On the other hand, generalized Snell's Law is applied to introduce additional reflection phase. Anomalous reflection is realized to steer the Vortex wave by 30 degrees.