Analysis, Optimization, and Characterization of Magnetic Photonic Crystal Structures and Thin-film Material Layers

Abstract

MPC (Magneto-Photonic Crystal) Optimisation is a feature-rich Windows software application designed to enable researchers to analyze the optical and magneto-optical spectral properties of multilayers containing gyrotropic constituents. A set of computational algorithms aimed at enabling the design optimization and optical or magnetooptical (MO) spectral analysis of 1D magnetic photonic crystals (MPC) is reported, together with its Windows software implementation. Relevant material property datasets (e.g., the optical spectra of refractive index, absorption, and gyration) of several important optical and MO materials are included, enabling easy reproduction of the previously published results from the field of MPC-based Faraday rotator development, and an effective demonstration-quality introduction of future users to the multiple features of this package. We also report on the methods and algorithms used to obtain the absorption coefficient spectral dispersion datasets for new materials, for which the film thickness, transmission spectrum, and refractive index dispersion function are known. Program summaryProgram Title: Optimisation of 1D Magnetic Photonic Crystals (alternatively, MPC Optimisation) Program Installation Files: available from https://drive.google.com/open?id=1P3UgIu6nbfbmqXexrbppeiSIffplE-uv Licensing provisions: Creative Commons Attribution-NonCommercial-3.0 Unported (CC BY-NC-3.0) Programming language: Visual C#, compiled using Microsoft Visual Studio .NET 2003Nature of problem: Calculation of the optical transmission, reflection, and Faraday rotation spectra in multilayer thin films containing gyrotropic constituents (magnetized material layers possessing magneto-optic properties); optimization of magnetic photonic crystal (MPC) designs aimed at achieving maximized transmission or reflection coincident with maximized Faraday rotation, according to sets of defined criteria; fitting of the experimentally measured transmission or reflection spectra to theory models; fitting of the absorption coefficient spectra of single-layer thin film materials using the data for optical transmission, film thickness, and refractive index spectra.Solution method: The developed programme exhaustively calculates multiple possible multilayer structure designs, based on the design structure type(s) defined prior to running optimisation. Complex-valued 4×4 transfer matrix method (accounting for all dielectric tensor components, including the non-diagonal terms responsible for gyrotropic effects) is implemented to compute the complex field amplitudes and optical intensities in either the transmitted or reflected left-hand and right-hand circularly-polarized eigenwaves propagated through the thinfilm-substrate structure.Restrictions: The program is designed for use in conjunction with reliable optical constant datasets for up to 3 component dielectric materials, one of which can be modeled as magnetic dielectric possessing Faraday rotation; metallic layers are not implemented. Embedded active-X controls enabling graphica...

Enhancement Magneto-optic Properties of Radio-Frequency-Magnetron-sputtered Bi-containing Ferrite Garnet-Type Thin-films using Oxygen plasma treatment and metal-oxide protective layers

“…To investigate the effects of post-deposition oxygen plasma treatment on the optical and magneto-optical behaviours of Bi2.1Dy0.9IG type thin films, we derived the optical absorption coefficients, measured the specific Faraday rotation and calculated the MO figure of merit at a certain spectral wavelength (532 nm). The transmission spectra of all annealed garnet layers were spectrally fitted with the modeled transmission spectra to determine the optical absorption on the garnet layers by using the MPC software reported in [39]. The plasma-treated samples showed slightly higher specific Faraday rotation at 532 nm compared to the non-treated garnet samples, and this was repeatedly observed in all batches of plasma treated annealed samples.…”