Optical waveguides are fabricated in Nd3+:Y3+:SrF2 crystals by a 1-kHz femtosecond laser using the double-line approach. Waveguides with different separations (10, 15, and 20 \mm m) between two consecutive optical breakdown tracks are produced, and their optical performances are explored by end-fire coupling to 780-and 532-nm lasers. Propagation loss of the waveguide with 20-\mm m separation is estimated. The microphotoluminescence and micro-Raman spectra indicate that the original fluorescence and lattice structure of the Nd3+:Y3+:SrF2 crystals are well preserved in the waveguide. Therefore, the obtained waveguide structures are promising candidate for application in integrated waveguide lasers.
© 2013 Chinese Optics LettersPDF Article