Abstract

Absence of full knowledge on resonant susceptibility (RS) of laser crystals leads to underestimation of different nonlinear optical effects (such as holorgraphic grating formation and others) which are very important for understanding the complicated laser dynamics and construction of new laser architectures. In the majority of previous experiments the resonant wave mixings (using nonlinearity of saturation of the working transition) in inverted Nd:YAG are explained by the gain grating (GG) formation (sec. for example. [1]). On the other hand, it is well known, that pumped and unpumped laser crystals have different refractive indexes due to difference in polarizability of excited and unexcited Nd₃ ions [2,3]. However. various investigation methods provide different values of the polarizability difference varying from 4.10⁻³nm³ [2] to 9.10⁻⁴ nm³ [3] for the well-studied Nd-dopcd materials.

© 1998 IEEE