Controlling asymmetric transmission in layered natural hyperbolic crystals

We explore the electromagnetic properties of a structure composed of two optically active materials—each layer contains a hyperbolic crystal with its anisotropy axis rotated with respect to the crystal surface. Through this, we can control the transmission spectra where at one frequency, light with a positive incidence angle is transmitted while it is absorbed for a negative incidence angle and the reverse occurs at a second frequency. Using a Gaussian beam analysis, we determine in which material layer the absorption occurs. In a radiating line current source study, we obtain tunable output collimated beams. From these discoveries, our structure can be applied as an efficient frequency or angle selector, demultiplexer, or filter.