Effect of optical losses on optical and magneto-optical properties of one-dimensional magnetophotonic crystals for use in optical isolator devices

Abstract

One-dimensional magnetophotonic crystal (1-D MPC) film composed of thin rare-earth iron garnet, SiO 2 and Ta 2O 5 films simultaneously exhibits very high optical transmittance and Faraday rotation. We investigated the structure of 1-D MPC, which by theoretical calculation has an optical isolation performance favorable from an industrial perspective. Furthermore, we considered, theoretically, whether it could be used as an optical isolator if a film had absorption. As a result, the structure of 1-D MPC film with satisfactory optical isolation has an industrially favorable structure by using a high refractive index material such as Si. It was also found that if the optical absorption (extinction coefficient κ) of a film was less than 0.000001, it did not affect the characteristics. This makes it very attractive for actual optical isolator fabrications.