Development and investigation of the performance of Tm:YAG and Tm:LuAG lasers excited with narrowing guide structured diode at 680 nm

Tm3+ lasers, which can be excited in the ranges of 785-808 nm, 1150 nm and 600-700 nm and emit at 2 𝜇m, are used in a wide range of areas such as health, industry, scientific research, military applications, and light shows. Tm3+ lasers are generally excited at 785 nm due to the cross-fading effect and easy access to the necessary equipment. From the past to the present, it has been observed that Tm3+ laser systems are quite rare at this wavelength due to the difficulty of accessing suitable pumping equipment to excite Tm3+ lasers at 680 nm. However, when the absorption band of Tm3+ lasers is examined, lasers excited at 680 nm are absorbed three times more than lasers excited at 785 nm, and it is seen that lasers excited at 680 nm have more cross-fading effect than lasers excited at 785 nm. In this study, Tm:YAG and Tm:LuAG laser systems were excited at 680 nm with recently developed high brightness 1 W narrow guide structure AlGaInP laser diodes. 20 different laser systems were established including 1.5% doped 9, 7.5 and 3 mm in length; 3% doped 7.5 and 3 mm in length; 6% doped 7.5 and 3 mm in length Tm:YAG lasers and 2% doped 9, 7.5 and 3 mm in length; 4% doped 7.5 and 3 mm in length; 6% doped 7.5 and 3 mm in length TmLuAG lasers. Continuous wave regime, wavelength change, dual wavelength radiation spectrum, M^2 measurement and Q switching pulse regimes were investigated for each system. In the investigations, the highest output power up to 332 mW and efficiencies up to 45% were obtained for Tm:YAG lasers in continuous wave regime. In the wavelength change made with a double-refractive prism, a wavelength change range of up to 216 nm was observed. Dual wavelength radiation was observed between 1878 and 2082 nm at the farthest power of 48 mW. In the Q-switching regime performed with SESAM, pulses with an energy of 2.83 𝜇J, a width of 0.872 𝜇s, a peak power of 1180 mW, and a frequency of up to 37.88 kHz were observed. For Tm:LuAG lasers, a maximum output power of up to 268 mW and efficiencies of up to 44% were obtained in the continuous wave regime. A wavelength change range of up to 208 nm was observed in the wavelength change made with a double-refractive prism. Dual wavelength radiation was observed between 1882 and 2066 nm at the farthest power of 55 mW. In the Q switching regime with SESAM, pulses with energy of 2.87 𝜇J, width of 1.36 𝜇s, peak power of 1207 mW, and frequency of up to 30.53 kHz were observed.