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Holmium laser output wavelength at atmospheric windows, water strong absorption bands and eye-safe area, can be used for medical laser, optoelectronic countermeasures, laser rangefinder and laser radar and other fields, can also be used as an optical parametric oscillation and optical parametric amplification pumped source, in order to achieve a longer mid-infrared band output. Using laser-pumped Tm Ho laser system can be achieved at room temperature 2μm high power laser output. In this paper from the spectral characteristics and laser experiments on Ho: YAP crystals were studied. In theory and spectral characteristics, this paper introduces the photoluminescence theory, crystal field theory, Judd-Ofelt theory and the rate equation. Measuring the Ho: YAP crystal at room temperature absorption spectra and fluorescence spectra, calculated using the Judd-Ofelt theory of Ho: YAP crystal JO intensity parameters, spectral intensity, spontaneous radiative lifetime, the effective absorption cross section and integral emission cross section, and in accordance FL formula to calculate the Ho 3 ions in the YAP crystal effective emission cross section, and according to Ho 3 ions effective absorption cross section and the effective emission cross section, calculates Ho: YAP crystal The gain section. Ho: YAP crystal JO number: Ω 2 = 1.85 × 10 -20 , Ω 4 = 4.08 × 10 -20 , Ω 6 = 2.32 × 10 -20 cm 2 , Ho 3 ion 5I7 level life is 4.87ms. According to the results, analysis of Ho: YAP laser material crystal as a light-emitting properties. In the laser experiments were carried out with diode laser-pumped Tm: YAP laser, Tm3-doped fiber lasers and Tm: YLF laser as the pump source Ho: YAP laser experimental study. For Tm: YAP laser pumped Ho: YAP laser, when injected into the pump light when power is 4.98W, 1.08W maximum continuous output power of the laser output; For Tm-doped fiber laser pumped Ho: YAP laser, when injected The pump power is 4.32W, the maximum output power of 0.41W continuous laser output; For Tm: YLF laser pumped Ho: YAP laser, in the case of continuous operation, to obtain the maximum output power of 5.49W laser output the repetition frequency of 10kHz operation of Q-case, the maximum pulse energy 0.53mJ, corresponding to a pulse width of 27ns. When the output mirror transmittance greater than 14%, the use of any of the above pump source Ho: YAP laser output wavelengths are 2118nm.
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