Efficient dual-wavelength Nd:LuLiF_4 laser

Abstract

We report an efficient continuous-wave (CW) and passively Q-switched dual-wavelength Nd:LuLiF 4 laser at 1314 and 1321 nm for the first time. Maximum CW output power of 6.08 W is obtained, giving an optical-to-optical conversion efficiency of 30.2% and a slope efficiency of 32.1%. Even using high doping V 3 :YAG as the saturable absorber to passively Q-switch the laser, stable dual-wavelength operation remains. Maximum pulse energy extracted from the resonator is 108.7 μJ at 17.2 kHz pulse-repetition rate, and maximum peak power is 885 W.

808-nm diode-pumped dual-wavelength passively Q-switched Nd:LuLiF4 laser with Bi-doped GaAs

“…Under the maximum output power, the beam quality parameter M 2 of the CW laser beam was measured to be 1.12 in tangential plane and 1.19 in sagittal plane, respectively, by using a 10.0/90.0 knife-edge method, indicating a nearly diffraction limited output beam and being better than that in Ref. [15]. While the M 2 factor for Q-switched laser beam was measured to be 1.19 in tangential plane and 1.26 in sagittal plane, respectively.…”

“…[18], lower slope efficiency and less output power were obtained than those in Ref. [15]. Then passively Q-switched Nd:LLF laser performance was investigated by inserting the Bi-GaAs into the cavity.…”

“…Unlike YLiF 4 crystal, the thermal conductivities of LuLiF 4 crystal are almost isotropic rendering less thermal stress during crystal growing processes [14]. 792 nm diode-pumped efficient continuous-wave (CW) and passively Q-switched dual-wavelength Nd:LuLiF 4 (Nd:LLF) laser at 1314 and 1321 nm was reported by Li [15], in which V:YAG was employed as saturable absorber. Bi-doped GaAs as saturable absorber was seldom investigated, especially in realizing Q-switched dual-wavelength laser operation.…”

1.31 and 1.32 μm dual-wavelength Nd:LuLiF4 laser

“…Here, in order to compare the experiment results with those in Ref. [5], these two output coupling transmissions were chosen. Further increasing the pump power, the FWHM of the laser spectrum in each wavelength became broader.…”

“…Dual-wavelength Nd:YLF lasers at 1312 and 1322.6 nm have been demonstrated by Louyer et al in 2003 [1]. In 2013, Li et al reported continuous-wave (CW) dual-wavelength Nd:LuLiF 4 (Nd:LLF) laser operation at 1314 and 1321 nm [5]. However, the PQS dual-wavelength Nd:LLF laser at 1.3 μm with V:YAG was only obtained with the 3% output coupling beyond a certain absorbed pump power.…”