Phase-matched UV generation at 01774 μm in KB_5O_8 · 4H_2O

Sixth-harmonic generation of the Nd:YAG laser frequency at 1.0642 μm has been achieved in KB(5) O(8) ˙ 4H(2) O by type-1 mixing the fundamental and fifth harmonic at room temperature. The phase-matching angles were measured to be (θ = 90°, φ = 68.5 ± 0.5°) and (θ = 80.0 ± 0.5 °, φ = 90°) in the x - y and y -z planes, respectively. Improved Sellmeier equations of this crystal are presented.