Diffraction efficiency in quasi-degenerate coupling in photorefractive materials
The aim of this work is to present theoretical analysis of the diffraction efficiency in sillenite BTO crystal, for mobile transmission gratings, where the effects of coupling beams are significant . In case of the degenerate coupling in photorefractive materials, the efficiency depends of the cryst...
| Autores: | , , , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2019 |
| País: | Argentina |
| Institución: | Universidad Nacional de La Plata |
| Repositorio: | SEDICI (UNLP) |
| Idioma: | inglés |
| OAI Identifier: | oai:sedici.unlp.edu.ar:10915/124389 |
| Acceso en línea: | http://sedici.unlp.edu.ar/handle/10915/124389 |
| Access Level: | acceso abierto |
| Palabra clave: | Física Photorefractive crystal Diffraction efficiency Case non-degenerate Concentration ratio Cristales fotorrefractivos Eficiencia de difracción Caso cuasi-degenerado Razón de concentración |
| Sumario: | The aim of this work is to present theoretical analysis of the diffraction efficiency in sillenite BTO crystal, for mobile transmission gratings, where the effects of coupling beams are significant . In case of the degenerate coupling in photorefractive materials, the efficiency depends of the crystal thickness, coupling coefficient and the input intensity ratio. In the non-degenerate coupling case, the diffraction efficiency also depends on the response time of the photorefractive medium. This response time is the function of concentration ratio, i.e., of the relation between acceptor numbers and donor numbers. The diffraction efficiency is obtained by using coupled wave equations in onBragg regime using Method Runge-Kutta of order 4 in Matlab. The analysis considers the nonuniformity of the gratings inside the crystal, the concentration ratio of the material and detuning frequency. |
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