A method to determine the focal length of a thermal lens and pumping laser beam waist in the gain medium in laser-diode-pumped solid-state lasers is presented. This method, using resonator transform circle theory, is both simple and reliable. The measured focal length of the thermal lens is used to calculate the beam waist of pumping laser inside the gain medium. The effect of the thermal lens on the output power is also measured and analyzed.

本文系统地介绍了Er. Yb玻璃的研究发展状况及其应用前景。同时测量了吸收光谱和发射光谱。

Frequency upconversion into green and red luminescence in erbium-ytterbium-codoped phosphate glass pumped with a 970 nm diode laser is presented. The red upconversion emission results from a two-photon excitation process. The green emission results from a two- or three-photon excitation process with the two-photon process dominating at low pumping power. Based on measurement of the excitation and emission spectra, a model of the three-photon excitation process has been developed. This model provides a good basis for explaining the effect of the three-photon process on the saturation of 1.54 mm laser power of Er, Yb-codoped phosphate glass laser.

Rate-equation analysis and experiments on a pulsed dual-wavelength Ti:sapphire laser are reported in the paper. A four-energy-level system with two lower-energy levels is put forward and numerical calculations are given. A simple optical setup with two sub-resonators is constructed, which yields a total energy from dual-wavelength lasers up to 41.8mJ. The largest tunable range is over 110nm. Laser characteristics of dual-wavelength pulses are observed. Experimental results are in accord with rate-equation-theory results.

提出了一种新的固体激光器的谐振腔结构，其主要特点是，在腔内引入一较短焦距的固定透镜，并将激光介质，即焦距可变的热透镜，置于它的焦点处，组成一特殊的两透镜组，利用变换圆图解方法分析表明，该透镜组具有光学‘镇定器’的作用；利用这种谐振腔，通过自适应地轴移调节一个腔镜，可以解决较大功率固体激光器在热透镜效应大幅度变化情况下的基本光学模的动力学稳定运行；同时，保持激光介质及两端镜处的基模光斑尺寸不变。