[22p-A402-1~13] 3.4 Laser system and materials (formerly 3.5)

[22p-A402-13] Development of output couplers for CO₂ laser pumped FIR lasers

〇Kazuya Nakayama¹, Ryo Yasuhara², Kenji Tanaka², Masaki Suzuki³ (1.Chubu Univ., 2.NIFS, 3.LaserMate)

Keywords:FIR laser, CO2 laser

For fusion plasma diagnostics and the development high-sensitive far-infrared (FIR) detectors, we have developed high-power and single-mode FIR molecular gas lasers in the wavelength range of 40 to 120 µm (frequency 2.5 to 7.5 THz). In this study, two types of output mirrors were designed and manufactured, one for CH₃OH lasers with wavelengths of 119 µm and 71 µm and the other for CH₃OD lasers with wavelengths of 57 µm and 48 µm. 12 layers of Ge/ZnS and 8 layers of Ge/CsI were coated on high resistivity Si substrates by vacuum deposition. The output mirrors have achieved an output improvement of about 10 to 50 % compared to conventional output mirrors.