Laser wavelength shift and dual-wavelength generation in continuous-wave operation of Ho:YAG laser pumped by thulium-doped fiber laser. (February 2022)

• Record Type: Journal Article
• Authors: Kwiatkowski, Jacek; Sotor, Jarosław
• Is Part Of: Optics & laser technology. Volume 146(2022)
• Publication Date: 2022-02
• Subjects: Mid-infrared lasers -- Ho:YAG -- Solid-state lasers; Optics -- Periodicals; Lasers -- Periodicals; Electronic journals; 621.366
• DOI: 10.1016/j.optlastec.2021.107544
• Languages: English
• ISSNs: 0030-3992

Abstract

Highlights: Simultaneous dual-wavelength laser generation with the same amplitude in Ho:YAG laser. Beam quality factor of M 2 not higher than 1.12 was measured for simultaneous lasing emission. Detailed spectral analyses of a Ho:YAG laser under continuous-wave operation was presented. Maximum output power of 14.43 W was obtained for a 20.3 W of incident pump power. Abstract: We present the output coupler transmission and radii of curvature (ROC )-dependent spectral analysis of a Ho:YAG laser, under continuous-wave operation, resonantly end-pumped by a thulium-doped fiber laser. At room temperature, with a 20.2% output coupling transmittance, 100 mm ROC, and 20.3 W incident pump power, the maximum output power is 14.43 W, corresponding to a slope and optical-to-optical conversion efficiency of 76.5% and 71.1%, respectively. For different output coupler transmissions, the laser emits at 2090, 2096, 2121, or 2128 nm along with simultaneous emission at two wavelengths. At a 19.43 W incident pump power, dual-wavelength laser generation, with the same amplitude, was obtained at 2096.73 and 2121.53 nm with good stability, and a signal-to-noise ratio of more than 35 dB at room temperature. A nearly perfect Gaussian beam profile for simultaneous lasing emission at two wavelengths with a beam quality factor of M 2 not higher than 1.12 was measured.