Research On Passive Q-switched Tm,Ho:LuVo₄ Laser Technology Based On WSe₂/WS₂ Material

The 2μm laser is located in the safe area of the human eye and the window band of the atmosphere,covers the absorption peaks of many atoms and molecules.It has broad application prospects in radar detection and material etching.In recent years,with the in-depth study of solid-state laser technology,Ho³⁺single-doped,Tm³⁺and Ho³⁺co-doped 2μm solid-state laser technology has gradually matured.Among of them,Tm³⁺and Ho³⁺co-doped 2μm solid-state lasers can use a laser diode of about800nm as a pump source,which has the characteristics of small size and simple structure.In this paper,two-dimensional WS₂ and WSe₂ materials are used as saturable absorbers,respectively,and the output characteristics of passive Q-switched Tm,Ho:LuVO₄ lasers are studied to achieve high pulse energy and short pulse duration2μm laser.First,the preparation of WS₂ and WSe₂ saturable absorbers was carried out in this paper.A homogeneous dispersion of two-dimensional WS₂ and WSe₂materials was prepared by ultrasonic pyrolysis,and the dispersion was uniformly spin-coated on one side of the Ca F₂plane mirror to make a saturable absorption mirror.The optical properties of two-dimensional WS₂ and WSe₂ materials in the 2μm band were measured The optical properties of two-dimensional WS₂ and WSe₂materials in the2μm band were measured and studied.The experimental results show that the two-dimensional WS₂ and WSe₂ materials have low saturation light intensity,large modulation depth,low nonlinear saturation loss,and are excellent saturable absorber materials.This work laid a preliminary foundation for the subsequent research of the Tm,Ho:LuVO₄ laser.Then,the research on the output characteristics of continuous wave Tm,Ho:LuVO₄ laser was carried out.When the laser cavity output mirror transmittance is 2%and the incident pump power is 11.12W,the output power of the Tm,Ho:LuVO₄laser is 3W,the corresponding light to light conversion efficiency is26.98%,and the slope efficiency is 27.6%,the center output wavelength of the laser is2075.6nm,the beam quality factor M_x² and M_y² are 1.11 and 1.06,respectively.Based on this,research on the output characteristics of passive Q-switched Tm,Ho:LuVO₄ lasers is carried out.Finally,the research on the output characteristics of passive Q-switched Tm,Ho:LuVO₄ lasers with WS₂and WSe₂ as saturable absorbers was carried out.When WS₂ is used as a saturable absorber,the threshold pump power of the Tm,Ho:LuVO₄laser is 2.12W,the maximum average output power is 263m W,the corresponding pulse width is 1.266μs,the pulse repetition frequency is 44.56k Hz,and the single pulse energy is 5.902μJ,the light to light conversion efficiency is 3.2%,the slope efficiency is 3.97%,and the laser output beam quality factor M_x² and M_y² are1.05 and 1.06,respectively.When WSe₂ is used as the saturable absorber,the threshold pump power of the laser is 4.697W,the maximum average output power is 500m W,the corresponding pulse width is 3.5μs,the pulse repetition frequency is 113.9k Hz,the single pulse energy is 4.21μJ,the light to light conversion efficiency is 2.17%and the slope efficiency is 4.78%and the laser output beam quality factor M_x² and M_y² are1.02 and 1.03,respectively.The output wavelength of the passive Q-switched Tm,Ho:LuVO₄laser is around 2057nm.