Metasurface Beam Deflector

Application ID: 115971


This model demonstrates how to simulate a metasurface beam deflector that uses anomalous refraction. The structure itself is a repeated array of six posts (so-called meta elements). The periodicity of the individual posts is 500 nm, so the full structure of six posts is 3 um wide. The posts are 1 um tall, and the structure is designed to operate at a free space wavelength of 1.55 um.

The cylindrical pillars are Silicon and the substrate is SiO2. The structure is designed so that incident light coming through the substrate at a normal angle of incidence will be refracted at prescribed angle - the anomalous refraction angle.

To model this using COMSOL we apply Periodic Condition boundaries in the x and y directions, combined with Ports of the periodic type in the z direction. The Diffraction Order subnodes on the Ports will fully account for the transmission and reflection into each allowed diffraction direction.

This model example illustrates applications of this type that would nominally be built using the following products: