Stable CW-operating waveguide lasers at room temperature in rare-earth-diffused lithium niobate

摘要

Abstract: A means of reproducibly fabricating stable cw channel waveguide lasers in rare-earth-doped Ti:LiNbO$-3$/ is demonstrated, through careful choice of the light propagation direction. Z-propagating waveguides have been fabricated in Nd:Ti:LiNbO$-3$/ and room-temperature cw laser operation has been obtained by pumping in the 800 nm-band, with greatly reduced photorefractive instability. The reduced photorefractive damage susceptibility in this waveguide configuration has been used to our advantage in the realization, for the first time, of a 980 nm-pumped laser in Er:Ti:LiNbO$-3$/. The device showed a lasing threshold of 10.5 mW of absorbed pump power and a slope efficiency of 8.5 percent. !18