Indium-modified Yb:KLu(WO4)(2) crystal: Growth, spectroscopy and laser operation

Identifier:  imarina:9242043

Handle: https://hdl.handle.net/20.500.11797/imarina9242043

Authors:  Serres, JM; Mateos, X; Loiko, P; Griebner, U; Petrov, V; Yumashev, K; Aguiló, M; Díaz, F

Abstract:
We report on the growth, spectroscopic and laser characterization of a novel monoclinic laser crystal, Yb,In:KLu(WO4)(2) (Yb,In:KLuW). The absorption, stimulated-emission and gain cross-section spectra of 3.5 at% Yb, 5.5 at% In-doped KLuW are determined at room temperature with polarized light and compared with those for Yb,In:KYW, as well as singly Yb-doped KLuW and KYW crystals. It is found that the introduction of In results in a decrease of the transition cross-sections and in a spectral broadening of the absorption and emission bands. Such a broadening is more pronounced for light polarization E parallel to N-p. For Yb,In:KLuW, the maximum sigma(abs) is 9.9 x 10(-20) cm(2) at 980.9 nm for E parallel to N-m and the corresponding bandwidth of the absorption peak is 3.7 nm. The radiative lifetime for Yb3+ ions is 237 +/- 5 mu s. The stimulated emission cross-sections are sigma(SE)(m)= 2.4 x 10(-20) cm(2) at 1022.4 nm and sigma(SE)(p) = 1.3 x 10(-20) cm(2) at 1039.1 nm corresponding to an emission bandwidth of > 30 nm and > 35 nm, respectively. The diode pumped N-g-cut Yb,In:KLuW microchip laser generated 4.11 W at 1042-1048 nm with a slope efficiency of 78%. The Yb,In:KLuW crystal is very promising for the generation of sub-100 fs pulses in mode-locked lasers due to its broadband emission characteristics. (C) 2016 Elsevier B.V. All rights reserved.