Microchip laser operation of Tm

Identifier:  PC:1131

Handle: https://hdl.handle.net/20.500.11797/PC1131

Authors:  Loiko, P.; Serres, J.M.; Mateos, X.; Yumashev, K.; Kuleshov, N.; Petrov, V.; Griebner, U.; Aguiló, M.; Díaz, F.

Abstract:
A microchip laser is realized on the basis of a monoclinic Tm,Ho-codoped KLu(WO4)2 crystal cut for light propagation along the Ng optical indicatrix axis. This crystal cut provides positive thermal lens with extremely weak astigmatism, S/M = 4%. High sensitivity factors, M = dD/dPabs, of 24.9 and 24.1 m-1/W for the mg- and pg- tangential planes are calculated with respect to the absorbed pump power. Such thermo-optic behavior is responsible for mode stabilization in the plano-plano microchip laser cavity, as well as the demonstrated perfect circular beam profile (M2 < 1.1). Maximum continuous-wave output power of 450 mW is obtained with a slope efficiency of 31%. A set of output couplers is employed to achieve lasing in the spectral range of 2060-2096 nm. The increase of output coupler transmission results in deterioration of the laser performance attributed to the increased up-conversion losses.