We have demonstrated a controllable dual-wavelength laser operation of a Nd:GdVO/Nd:YVO composite crystal at 1063 and 1064 nm with in-band diode pumping around 912 nm by simply varying the operational temperature of the laser diode. When compared with the traditional 808 nm pumping, this approach offers simpler laser system, more flexibility in dual-wavelength operation, higher efficiency and lower thermal lensing effect. The laser produced an output power of <4W with a slope efficiency of <45% and 1:1 spectral power ratio.
Thermal lensing effect in a Nd:GdVO4 laser system operating at 1063 nm with in-band pumping at 912 nm was studied. The thermal lensing strength was experimentally measured and the determined focal power was as strong as 9 m-1 at 11.3 W of output power. The sensitivity factor of the thermal lens was calculated to be as small as M = 0.503 m−1/W for the pump spot size radius of ~197 μm. The present work indicates that in-band pumping at 912 nm can offer further power scaling opportunities for the Nd:GdVO4 lasers due to the strongly reduced thermal lensing effect.
We report what we believe is the first demonstration of a continuous-wave Nd:YLF laser under in-band diode pumping at 908 nm. The laser produced the maximum average output power of ~750 mW at 1047 nm. The maximum slope and optical-to-optical efficiencies were 39.5% and 64.6%, respectively, with respect to the absorbed pump power. The maximum output power was limited by the available absorbed pump power and not the thermal effects. The results that are presented in this work are preliminary and further work is in progress to improve the efficiency of the laser system.
We have demonstrated the highest conical refraction (CR) laser output power to date by placing a CR crystal inside of a diode-pumped Nd:YVO laser cavity. The CR crystal did not have a significant influence on laser output power as well as efficiency. The CR laser produced the maximum output power of 3.68 W with the slope efficiency of 42 % and opticalto- optical efficiency of 34 %. Therefore, this approach could be an attractive pathway for further power scaling of the CR lasers.