RESEARCH OF THERMO-OPTICAL INHOMOGENEITIES IN Yb-Er GLASS AT DIODE PUMPING

Subject of Research. Investigation method of thermo-optical distortions in solid-state lasers was developed and presented. The method can be easily used for research of small diameter (approximately 2 mm) active elements. Method. The experimental method described in this paper is based on the registration of deviation of the energy center of the probe beam passing through the thermally stressed active element. Main Results.  We have presented experimental results of the thermal lens optical power research in the active element made of Yb-Er glass pumped transversely by a laser diode in the following modes: without generating, free-running and Q-switching. We have submitted obtained dependences of the optical power on the pumping energy. The measurements have been performed for the two polarization components at two wavelengths (632.8 nm and 1550 nm) showing the absence of explicit astigmatism of the thermal lens. Practical Relevance. Knowledge of the thermal regime of such lasers gives the possibility for more precise calculation of the resonator parameters in terms of the thermal lens occurrence. 

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