الخلاصة:
Laser sources are the most important elements in a channel of optical telecommunications.
However these are unstable, and have fluctuations. To overcome this drawback it is necessary to place an optical isolator in the output of the cavity which will eliminate reflections.
Photonic crystals are materials whose optical properties are used to manipulate the light across the wavelength. These crystals are structures whose refractive index varies periodically in one, two or three directions in space.
When combined magneto-optical materials and photonic crystals, it appears the new components based on magneto photonic crystals, which exalt the non-reciprocal effects of the propagation.
This work is a contribution to digital studies magneto photonic crystals, we simulated planar structures of photonic band gap materials we focus on their physical properties such as Bands diagram and Gaps map.
These simulations are designed to check the position of the photonic band gap in the studied structure. Our structure is a planar photonic crystal consisting of a magneto-optical material layer referred to as BIG (bismuth garnet ferrite or called bismuth iron garnet) deposited on a layer of GGG (gadolinium garnet and gallium), in a triangular structure and then for a square structure. We study the optical fibres in BIG material, it begins with a conventional optical fibre structure, and we move to a study of magneto photonic crystal fibre based BIG. It was these simulations to study the mode coupling TE-TM, which is originally identical to the Faraday rotation to obtain a non-reciprocal effect in guided configuration.
By varying the gyrotropy, we observed its effect on the coupling efficiency, and changes in other physical parameters affect the conversion rate TE-TM. The coupling output of TE-TM depends on the birefringence and Faraday rotation, for this we made another simulation to determine the birefringence and consequently to find the Faraday rotation which is the main objective of our work. To perform these simulations we used two software of Rsoft CAD, the first module is called BandSOLVE which is based on the plane wave method (PWE), and the second called BeamPROP, based on the beam propagation method (BPM).
We show a significant increase of the Faraday rotation which improves the performance of the optical isolators.
