High optical performance and practicality of active plasmonic devices based on rhombohedral BiFeO₃

Abstract

Abstract First principles calculations of electronic and optical properties of multiferroic oxide BiFeO 3 are used in combination with a plasmonic device model of optical switch to show that a BiFeO 3 based device can have much better performance than devices based on existing materials. This arises from the combination of octahedral tilts, ferroelectricity and G‐type antiferromagnetism in BiFeO 3 leading to a strong dependence of the optical refractive indices on the orientation with respect to the polarization. A prototype of a plasmonic resonator with an R‐BFO thin film layer is used as an example and shows excellent switch and modulation responses. The proposed approach provides potential opportunities to develop high performance nanophotonic devices for optical communication.