High-efficiency 5%Tm:KLu(WO₄)₂N_m-cut minislab laser

Abstract

We report a high-efficiency room-temperature 5%Tm:KLu(WO4)2 laser relied upon the gain slab-shaped crystal of volume less one and half cubic millimeter. Continuous-wave output power of 10.4 W at 1907 nm for 34.2 W of diode pump power has been demonstrated, with optical and slope efficiencies being of 31 and 43%, respectively. Thermal coefficient of optical path was evaluated also, TCOP (E || Np) ∼ –2×10-6.

Characterization of the thermal lens in 3 at.%Tm:KLu(WO4)2and microchip laser operation

“…It has good spectroscopic and thermal properties, which result in highly efficient lasing in the continuous-wave (CW) [2] and pulsed regimes [3,4]. Power scaling has also been attempted in thin-disk [5] and mini-slab [6] geometries showing the great potential of this laser material when using powerful diodes as a pump source.…”

Thermal lensing inNm-cut monoclinic Tm:KLu(WO4)2laser crystal

“…Thulium-doped double tungstates (DTs) like KLu(WO 4 ) 2 , KLuW, are appropriate materials for diode-pumped solidstate lasers emitting in the vicinity of 2 µm [1], the region of interest for medical applications, remote sensing and pumping of optical parametric oscillators. Tm-doped DTs are characterized by intense and wide polarized absorption/emission bands [2,3], which results in efficient diode pumping [4,5], polarized laser emission [1], wide-range tuning of laser emission [6,7], as well as generation of ultrashort pulses [8,9]. In addition, high concentrations of Tm 3+ are available without luminescence quenching and lattice distortion [1,2], which is important for mini-and microchip lasers [5,10] and thin-disc systems [11].…”

“…Tm-doped DTs are characterized by intense and wide polarized absorption/emission bands [2,3], which results in efficient diode pumping [4,5], polarized laser emission [1], wide-range tuning of laser emission [6,7], as well as generation of ultrashort pulses [8,9]. In addition, high concentrations of Tm 3+ are available without luminescence quenching and lattice distortion [1,2], which is important for mini-and microchip lasers [5,10] and thin-disc systems [11]. Several efficient cross-relaxation processes for Tm 3+ -pairs allow one to obtain a luminescence quantum yield approaching 2 [2].…”

Thermal-Lens-Driven Effects in $N_{\mathrm {g}}$ -Cut Yb-and Tm-Doped Monoclinic KLu(WO4)2 Crystals

“…In addition, high concentrations of active ions are possible without luminescence quenching and lattice distortion [11] which is important for mini-and microchip lasers [12,13], and thindisk configurations [14]. This is especially true for potassium luthetium DT which can be doped with thulium and ytterbium continuously up to 100at.% due to well matching of ionic radii of eight-fold coordinated Lu 3+ , Yb 3+ and Tm 3+ [1].…”