Optical circuit elements from anisotropic films

Anisotropic films provide a means to achieve optical circuit elements that are relatively independent of incident angle. This observation opens up a variety of circuit synthesis methods for implementing optical devices with important properties. We showed filter and anti-reflection coating examples for TM polarization that are robust to variation in the angle of incidence. Duality would lead to equivalent series capacitors and shunt inductors for TE polarization, if a suitable anisotropic permeability could be achieved (e.g., ferromagnetic materials). Practical realizations, in addition to metals/dielectrics, could have other material options, for example, plasmonic/polaritonic materials and semiconductors, depending on the operating frequency [7].