Adjustable Faraday rotation by using engineered one-dimensional magneto photonic crystals

Abstract

We investigated the adjustability and enhancement of magneto-optical Faraday rotation in one-dimensional magneto photonic crystal. The Faraday rotation can be adjusted through optical contrast ratio engineering in the resonator structure via equivalent layers theory. Also, simultaneous enhancement of the transmission magnitude and Faraday rotation of the structure can be obtained by optimizing the optical contrast ratio-magnetic defect layer thickness product. In a special design of magneto photonic crystal which consists of SiO 2 and Ta 2O 5 as the basic element of the resonator and Bi substituted yttrium iron garnet as the defect magnetic layer, by changing the optical contrast ratio from 1.43 to 1.09, the Faraday rotation can be adjusted from −3.35 to −0.74 deg in 65 nm wide range of wavelength. Finally, in the case which the optical contrast ratio optimized at 1.22 and the thickness of magnetic defect layer changed to one quarter of design wavelength, dramatic simultaneous enhancement of Faraday rotation and transmission magnitude can be obtained succesfully (the Faraday rotation and transmittance have their maximum value, −11.77 deg, and 99.67%).