Abstract

Potassium Lithium Niobate (KLN) has excellent potential as a non-linear medium for direct second harmonic generation (SHG) of semiconductor diode lasers. KLN crystallises in a tungsten bronze structure and space group P4bm within the compositional range K_3−yLi_2−x+yNb_5+xO_15+2x, 0.15 <X <2, -0.5 <Y <0.6. It exhibits only one ferroelectric transition from a paraelectric to ferroelectric phase well above room temperature at a Curie point of around 420 °C. Previous results indicate that KLN possesses appropriate birefringence for non-critical phase matching (NCPM) in the wavelength range of interest and large non-linear optical coefficients for efficient SHG output at sub-milliwatt pump power levels [1].

© 1998 IEEE