Laser damage studies of ZnS via neutral Zn particle emission
Emission of neutral atoms from ZnS surfaces due to laser irradiation has been observed at power densities two orders of magnitude below the single pulse damage threshold of the material. We have measured the velocity distribution and absolute yield of neutral Zn atoms generated by exposure of ZnS single crystals to XeCl excimer laser irradiation (308 nm) using time-of-flight and high-resolution two-photon laser-induced fluorescence spectroscopy. The distributions are in agreement with Maxwell-Boltzmann distributions. The characteristic temperature increases from 2000 to 9000 K as the fluences are raised from 17 to 80 mJ/cm/sup 2/, respectively. The absolute Zn yield also increases from 10/sup 8/ to 10/sup 12/ atoms per laser pulse as the laser fluence is increased. The results suggest formation of a plasma that interacts with the surface and leads to catastrophic failure. For consecutive laser shots at constant laser fluences, a nearly exponential increase in the Zn particle density is observed, yet visible damage did not occur until 150,000 laser shots. Our results show that neutral particle emission is of considerable importance in the identification of fundamental damage mechanisms and that microscopic damage occurs far below the single-pulse damage threshold. 4 refs., 2 figs.
- Research Organization:
- Argonne National Lab., IL (USA); Lawrence Livermore National Lab., CA (USA)
- DOE Contract Number:
- W-31109-ENG-38; W-7405-ENG-48
- OSTI ID:
- 6594671
- Report Number(s):
- CONF-881002-33; ON: DE89004212
- Resource Relation:
- Conference: 35. national vacuum symposium and 4th international laser science conference, Atlanta, GA, USA, 2 Oct 1988; Other Information: Portions of this document are illegible in microfiche products
- Country of Publication:
- United States
- Language:
- English
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Analysis of ion-bombarded and laser-irradiated surfaces of ZnS and Zn via two-photon high-resolution laser-induced fluorescence spectroscopy
Analysis of ion-bombarded and laser-irradiated surfaces of ZnS and Zn via two-photon high-resolution laser-induced fluorescence spectroscopy
Related Subjects
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
OPTICAL EQUIPMENT
DAMAGE
EMISSION
LASER POWER TRANSMISSION
LASERS
NEUTRAL PARTICLES
ZINC SULFIDES
CHALCOGENIDES
EQUIPMENT
INORGANIC PHOSPHORS
PARTICLES
PHOSPHORS
POWER TRANSMISSION
SULFIDES
SULFUR COMPOUNDS
ZINC COMPOUNDS
420300* - Engineering- Lasers- (-1989)
656003 - Condensed Matter Physics- Interactions between Beams & Condensed Matter- (1987-)