Diode-pumped Er:SrF₂ laser tunable at 27 μm

Feature issue introduction: mid-infrared optical materials and their device applications

“…In the 2-3 μm regime, low-phonon-energy crystals and glasses with rare earth doping are promising lasing media. Švejkar et al reported a tunable mid-IR laser using erbium-doped SrF 2 crystals as a gain medium [29]. Taking advantage of the reduced non-radiative recombination in low-phonon-energy fluorides compared to oxides, the Er:SrF 2 laser operates at room temperature with a maximum output power of 1.3 W and a slope efficiency of up to 9.2%.…”

Temperature distribution and the laser performance of LD end-pumped LuYSGG/Er:LuYSGG composite crystal

“…Some matrix crystals that are suitable for doping with rare earth ions include Y 3 Al 5 O 12 , 7,8 YAlO 3 , 9 Y 3 Ga 5 O 12 , 10 Gd 3 Ga 5 O 12 , 11 Y 3 Sc 2 Ga 3 O 12 , 12 Gd 1.17 Y 1.83 Sc 2 Ga 3 O 12 , 13 Lu 2 O 3 , Y 2 O 3 , 14,15 CaF 2 , 16 SrF 2 , 17 and LiYF 4 . 18 Among them, the oxide and sesquioxide crystals are favored by researchers owing to their good chemical stability, excellent mechanical property, and high thermal conductivity.…”

“…5 In addition, some nonlinear crystals, such as ZnGeP 2 and CdSe, have low absorption loss in the 2.7-3.0 μm waveband, enabling the 2.7-3.0 μm laser to be utilized as an ideal pumping source for optical parametric oscillation (OPO) and optical parametric generation (OPG) to induce mid and far infrared laser operated at 3.0-5.0 μm and 8.0-14.0 μm, respectively. 6 Some matrix crystals that are suitable for doping with rare earth ions include Y 3 Al 5 O 12 , 7,8 YAlO 3 , 9 Y 3 Ga 5 O 12 , 10 Gd 3 Ga 5 -O 12 , 11 Y 3 Sc 2 Ga 3 O 12 , 12 Gd 1.17 Y 1.83 Sc 2 Ga 3 O 12 , 13 Lu 2 O 3 , Y 2 O 3 , 14,15 CaF 2 , 16 SrF 2 , 17 and LiYF 4 . 18 Among them, the oxide and sesquioxide crystals are favored by researchers owing to their good chemical stability, excellent mechanical property, and high thermal conductivity.…”

Mid-infrared lightly Er3+-doped CaF2 laser under acousto–optical modulation

“…Besides low cost, direct generation approach can also take the advantage of commercial laser diode (LD). To date, the majority of studies on Er 3+doped lasers are largely based on Er:YAG, [8] Er:YSGG, [9,10] Er:GGG, [11] Er:CaF 2 , [6] Er:SrF 2 , [12] etc. To reduce the adverse effects of self-terminating transition, co-doped with deactivated ions or heavily Er 3+ -doped laser crystals are more inclined to be explored.…”