Wavelength and pulselength dependence of laser conditioning and bulk damage in doubler-cut KH2PO4

Conference · Fri Oct 28 04:00:00 EDT 2005

OSTI ID:877936

Adams, J J; Bruere, J R; Bolourchi, M; Carr, C W; Feit, M D; Hackel, R P; Hahn, D E; Jarboe, J A; Lane, L A; Luthi, R L; McElroy, J N; Rubenchik, A M; Stanley, J R; Sell, W D; Vickers, J L; Weiland, T L; Willard, D A

An experimental technique has been utilized to measure the variation of bulk damage scatter with damaging fluence in plates of KH{sub 2}PO{sub 4} (KDP) crystals. Bulk damage in unconditioned and laser-conditioned doubler-cut KDP crystals has been studied using 527 nm (2{omega}) light at pulselengths of 0.3-10 ns. It is found that there is less scatter due to damage at fixed fluence for longer pulselengths. In particular, there is {approx}4X increase in fluence for equivalent scatter for damage at 2{omega}, 10 ns as compared to 0.30 ns in unconditioned KDP. The results for the unconditioned and conditioned KDP show that for all the pulselengths the scatter due to the bulk damage is a strong function of the damaging fluence ({phi}{sup -5}). It is determined that the 2{omega} fluence pulselength-scaling for equivalent bulk damage scatter in unconditioned KDP varies as {tau}{sup 0.30{+-}0.11} and in 3{omega}, 3ns ramp-conditioned KDP varies as {tau}{sup 0.27{+-}0.14}. The effectiveness of 2{omega} and 3{omega} laser conditioning at pulselengths in the range of 0.30-23 ns for damage induced 2{omega}, 3 ns is analyzed in terms of scatter. For the protocols tested (i.e. peak conditioning irradiance, etc.), the 3{omega}, 300 ps conditioning to a peak fluence of 3 J/cm{sup 2} had the best performance under 2{omega}, 3 ns testing. The general trend in the performance of the conditioning protocols was shorter wavelength and shorter pulselength appear to produce better conditioning for testing at 2{omega}, 3 ns.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA
• Sponsoring Organization: USDOE
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 877936
• Report Number(s): UCRL-PROC-216743
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
LASERS
PERFORMANCE
PLATES
TESTING
WAVELENGTHS