Development and performance investigation of in-band diode pumped Tm:YAG and Tm:LuAG solid-state laser systems

In this thesis study, laser diodes developed in recent years and frequently used in telecom applications with high brightness in the 1,6 μm region and Tm3+ doped lasers were excited. Using these laser diodes, solid-state laser systems established with 10 different Tm:YAG and 10 different Tm:LuAG crystals were excited and their performances in continuous-wave and pulsed regimes were investigated. Results up to 189 mW output power and 63% efficiency were obtained from Tm:YAG lasers (with 1 W input power). In the Q-switched regime, the shortest pulses with a width of 1.09 μs and a repetition frequency of 22.54 kHz were obtained. The highest pulse peak power in these systems was 2.03 W and the pulse energy was 2.35 μJ. Results up to 147 mW output power and 68% efficiency were obtained from Tm:LuAG lasers (with 1 W input power). In the Q-switched regime, the shortest 1.99 μs wide, most frequent 27.46 kHz repetition frequency pulses were obtained. The highest pulse peak power in these systems was 0.56 W and the pulse energy was 1.42 μJ. In addition, wavelength change dynamics were examined and changes up to 204 nm (between 1871 nm and 2075 nm) were observed with Tm:YAG lasers and up to 159 nm (between 1924 nm and 2083 nm) with Tm:LuAG lasers. When solid-state thulium lasers are excited with the appropriate wavelength, they can emit radiation in the 2 μ region. Lasers in the 2 μ region are lasers that can emit radiation in the eye-safe region. These lasers exhibit high absorption properties in water and are widely used in many areas such as LIDAR systems, microsurgery, polymer, semiconductor and metal processing, defense industry, gas detection industries due to this feature effect and spectral properties. They provide meteorological data with long-range detections such as wind speed measurement, water vapor, carbon dioxide concentration detection. Again, considering that the main component of the tissue is water, they can show a penetration depth of micrometer level in the tissue, thus providing a very precise cutting of the tissue in surgical operations that require high precision. It is thought that the lasers developed in this thesis will attract great interest especially in areas such as LIDAR and spectroscopy.