Efficient 2-μm laser oscillation of 5% Tm³⁺: KLu(WO₄)₂disks and 5% Tm³⁺: KLu(WO₄)₂/KLu(WO₄)₂composite structures

Optical spectroscopy of Eu3+ ions doped in KLu(WO4)2 single crystals

“…In particular, the KLu(WO 4 ) 2 (KLuW) crystal is very suitable host for Yb and Tm ions [4]. Indeed Yb-and Tm-doped double tungstates (DTs), KRE(WO 4 ) 2 proved to be more attractive for intermediate power levels and laser action has been demonstrated in various active ions like Yb: KLuW [5][6][7] and Tm: KLuW [8][9][10] using a commercially available diode laser.…”

“…The monoclinic Potassium rare-earth double tungstates KRE(WO 4 ) 2 (KREW, being RE=Y, Gd and Lu) hosts stand out because they exhibit high absorption and emission cross-sections when doped with active lanthanide ions, partly due to the strong anisotropy of these biaxial crystals [1][2][3][4][5][6][7][8][9][10]. They can also be doped with high concentrations of the active ions without substantial fluorescence quenching [1].…”

High-efficiency lasing and spectroscopy of domestic 1%Nd:YAG and 1%Ho:YAG ceramics

“…Lasing spectra were measured with an MDR-24 monochromator, FR-185 photoresistor and selective Unipan-233 nanovoltmeter employed as a pre-amplifier; the spectral resolution was ~0.5 nm. In general, the experimental scheme is rather close to the scheme described in [13] except for several technical improvements related to the conditions of thermal stabilization of diode bars and active elements.…”

“…The cavity was formed by a highly reflecting mirror on a surface of a 250-µm-thick crystal of double potassium -lutetium tungstate 5%Tm:KLuW [13] and a partially transmitting mirror (T out = 0.6% in the range 1.85 -2.1 µm) deposited on the external surface of the ceramics. All optical surfaces inside the cavity had antireflection coatings in the spectral range of 1.85 -2.1 µm (with the residual losses on each surface of at most 0.1% in the range 1.85 µm and ~0.5% in the range 2.1 µm).…”

“…The lens made of fused KI silica with a focal length of 18 mm was placed at equal distances from the ceramics and disk element, and the physical cavity length was 50 mm. The active disk element (5%Tm:KLuW) was pumped by collimated radiation from two arrays of laser diodes (at a wavelength λ p = 806 nm) as in [13]; the diameter of the pump beam was 0.95 mm. For reducing thermal fluxes all measurements were performed in a quasi-cw regime with the duty factor of 14 %, the duration of current pulses of diode pumping was 7 ms at a pulse repetition rate of 50 ms.…”