Comparison of parameters of q-switching saturable absorbers estimated by different models and the impact of accuracy of input data on the results of the estimation

•Comparative analysis of different models was conducted and the one was chosen.•The impact of the accurate determination of the input data was analysed.•Taking unsaturable losses from the absorption spectra results in higher accuracy.•Principal parameters of Co2+:YAG saturable absorber at 1.33μm were estimated. Descriptions of the main classical models used to estimate the principal parameters of q-switching saturable absorbers are presented. On the basis of these models comparative analysis of q-switching saturable absorbers was done and the best one chosen. Additionally the impact of the accurate determination of the input data such as transmission, thickness and refractive index on the principal parameters was analysed. In order that the results of this analysis are useful not only from theoretical but also from practical point of view a complete setup for investigation of saturation of absorbers was built and investigations of three types of q-switching saturable absorbers Cr4+:YAG, V3+:YAG and Co2+:YAG were carried out. According to the knowledge of the authors the principal parameters of Co2+:YAG saturable absorber at 1.33μm wavelength are presented herein for the first time.