Properties Study On Magneto-Optical Photonic Crystals

Photonic band gap and localization are the important features in photonic crystals (PC). Magneto-optical crystals, which contains magnetic material and dielectric layers, not only has photonic crystals properties, but also has magneto-optical effect. It can be used to make optical isolators, modulators, optical switches and other optical devices. Based on the transfer matrix method, we investigated the characteristics of one-dimensional (1D) mirror symmetry PC, 1D magneto-optical crystals. We found that the structure adjusted can enhance the transmission characters and faraday effects.First, we investigated the properties of 1D PC with mirror symmetry. The defects are introduced in the position of mirror symmetry. When the defect location is fixed, there are always two defect modes in the band gap and the modes move along the longer wavelength with increasing the thickness of the defect. When the location of the defect layer with the same thickness is from the axis of symmetry, the defect modes reduce. When the refractive index changes, the change law of defect modes is identical with the change of thickness.Then, we investigated the transmission properties and faraday effects in 1D magneto-optical crystals. We designed a variety of magneto-optical crystals, such as single layer, double layers, multi-layers magnetic material crystals. By changing the number of layers, we found that there is a strong dependence between the faraday rotation angle and layers. With the increasing of the layers, faraday rotation angle enhances, but the transmission reduces. The max value of faraday rotation angle is 44.7°in these structures.Finally, we researched the influence of incident angle on faraday rotation angle. We found that the incidence angle can not affect faraday rotation angle, but changes the wavelength location of the transmission spectrum.