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arXiv · 0905.3125

Orientation of Nd$^{3+}$ dipoles in yttrium aluminum garnet: A simple yet accurate model

Sylvain Schwartz·Gilles Feugnet·Maxence Rebut·Fabien Bretenaker·Jean-Paul Pocholle
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Abstract

We report an experimental study of the 1064nm transition dipoles in neodymium doped yttrium aluminum garnet (Nd-YAG) by measuring the coupling constant between two orthogonal modes of a laser cavity for different cuts of the YAG gain crystal. We propose a theoretical model in which the transition dipoles, slightly elliptic, are oriented along the crystallographic axes. Our experimental measurements show a very good quantitative agreement with this model, and predict a dipole ellipticity between 2% and 3%. This work provides an experimental evidence for the simple description in which transition dipoles and crystallographic axes are collinear in Nd-YAG (with an accuracy better than 1 deg), a point that has been discussed for years.

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Sylvain Schwartz, Gilles Feugnet, Maxence Rebut, Fabien Bretenaker, Jean-Paul Pocholle. 2009-05-19. Orientation of Nd$^{3+}$ dipoles in yttrium aluminum garnet: A simple yet accurate model. https://doi.org/10.1103/physreva.79.063814

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