Dependences of energy damage thresholds on radiation parameters and geometry for KGSS 0180 phosphate neodymium glass have been studied. Laser-induced damage threshold dependences on the pulse duration for the range of 1.5-20 ns for KGCC 0180 and K8 glasses are: ε_kgss = 16 τ^1/2 ε^K8 = 18 τ^1/2(J/cm², when τ is in nanoseconds). Damage thresholds for the entrance and exit surfaces of KGSS 0180 glass samples have been measured when the samples were irradiated by a P-polarized beam at a Brewster's angle: ε_ent ≈ 48 J/cm²; ε_ex J/cm². As has been found out, the threshold energy density of the beam in the case of Brewster's incidence to the exit surface of the sample is almost 1.5 times lower than in the case of a normal incidence. Testing techniques for detection of platinum micro-inclusions in the laser glass have been developed. The energy threshold for Pt-inclusions explosion has been determined at ε_tr ≈ 2.5 J/cm² under laser pulse duration of 7 ns. Over 70 KGSS 0180 glass samples have been tested. It has been shown that platinum-induced damage was absent only in 25% of glass melts out of the entire tested amount. An averaged concentration of inclusions was N_pt ~ 5 liter^-1. Concentration of micro-inclusions in the last KGSS 0180 batch (2006 year) is ~ 1 liter^-1.

Date Published: 4 April 2007
PDF: 10 pages
Proc. SPIE 6610, Laser Optics 2006: Solid State Lasers and Nonlinear Frequency Conversion, 66100O (4 April 2007); doi: 10.1117/12.740014

Published in SPIE Proceedings Vol. 6610:
Laser Optics 2006: Solid State Lasers and Nonlinear Frequency Conversion
Vladimir I. Ustyugov, Editor(s)