Nature of the temperature dependence of the lasing efficiency of erbium laser glasses and the mechanism of the influence of sensitisers on this efficiency

A study was made of the influence of an elevated temperature on the lasing efficiency of ytterbium – erbium phosphate glasses, including the influence of additional sensitisation with neodymium or chromium ions. Temperatures below 200°C had practically no influence on chromium-free glasses. In the case of glasses containing chromium the deterioration of the parameters with increase in temperature was the result of a fall of the quantum efficiency of energy transfer in the chromium – ytterbium pair and also of an increase in nonradiative losses associated with the presence of the divalent chromium impurity.