types of optical isolator for ac transmission

The width of transmission region inside the photonic band gap (PBG) is wider for TM-mode. By the way, the possibility of obtaining both large Faraday rotation and high transmission has been provided for both TE and TM polarizations. Specifically, we have analyzed the influence of the incident angle in order to show the difference between TE- and TM-polarized lightwaves. In the present work, we have theoretically investigated the optical and magneto-optical spectra of quasi-periodic magnetic-dielectric multilayers composed by Ce:YIG and Si organized in accordance to the Octonacci sequence. Integrable optical isolators can be accessed by using the two proposed one-dimensional magneto-photonic crystal structures instead of the bulk type magneto-optical materials in bulk type optical isolator in commerce. Regarding the other structure, when the angle between applied magnetic field and optical axis was set as 32.7°, optical isolation reached 0.85 nm broad with total thickness of 11.54 μm, the Faraday rotation angle fluctuated from 45.0°~48.55° and the transmittance ranged from 98.85%~100%. This structure with 43 layers is applicable in the practical application and fabrication. For the first structure, when the angle between applied magnetic field and optical axis was set as 52.0°, it could realize the optical isolation around 0.95 nm with total thickness of 7.96 μm, possesses Faraday rotation angle and transmittance wave were at 45°~50.65° and 97.01%~99.96%. The 4×4 transfer matrix method was used to investigate the optical isolation property of two different one-dimensional magneto-photonic crystal structures. Then the obtained results may have potential applications in designing the multi-function single magneto-optical devices such as multiple Faraday rotators and wavelength division multiplexing systems. These wavelengths are currently used in telecommunication systems. However, the unique features of multichanneled enhanced Faraday rotations are obtained for different configurations of a multiple magnetophotonic heterostructure and the most suitable one to simultaneously support the both resonance wavelengths of 1.3 μm and 1.55 μm are introduced. It is shown that in a simple magnetophotonic heterostructure constituted of two different periodic structures, the enhanced Faraday rotation associated with high transmittance at a desired wavelength can be realized with specifying optimized repetition numbers and adjusting the thicknesses of the substructure layers. Transmittance magneto-optical responses of one-dimensional magnetophotonic heterostructures are investigated using 4 by 4 transfer matrix method. The information achieved by this research can be useful to fabricate a variety of graphene-based photonic systems and magneto-optical integrated devices such as miniaturized isolators and circulators. By calculation of light intensity distribution inside the structure at resonance wavelengths, we present consistent qualitative interpretation of the analytical results. In addition, the transmission coefficients and the Faraday rotation angles of these states are calculated and compared with each other.

Also, threshold states for merging the defect modes are determined for different amounts of these parameters. Results show that for specific repetition numbers of surrounding and middle cells of the structure, a defect mode is split into two completely separated modes. The numerical relation of resonances and splitting condition of them are determined in this structure. The interaction of dual-micro-cavity defect modes in a one-dimensional photonic crystal consisting of graphene layers is studied by using the transfer matrix method.

Types of optical isolator for ac transmission