Fabrication and characterization of periodically poled lithium niobate waveguide using femtosecond laser pulses

We present in this letter the fabrication and characterization of thermally stable type II waveguides in Z-cut periodically poled lithium niobate crystals. The waveguides were fabricated by using a femtosecond laser and were utilized for second harmonic generation. Our experiments have shown that a quasiphase matching wavelength of 1548.2 nm, a tuning bandwidth of 2 nm, and a tuning temperature range of 150.4 +/- 1.6 degrees C can be achieved. (C) 2008 American Institute of Physics.