Izvorni znanstveni članak
Nitrogen laser beam interaction with copper surface
Višnja Henč-Bartolić
; University of Zagreb, Faculty of Electrical Engineering and Computing, Division of Applied Physics, Unska 3, 10000 Zagreb, Croatia
Željko Andreić
; Rudjer Bošković Institute, Dept. of Material Science, Thin Films Laboratory, Bijenička 54, 10000 Zagreb, Croatia
Mirko Stubičar
; University of Zagreb, Faculty of Science, Dept. of Physics, Bijenička 32, 10000 Zagreb, Croatia
H.-J. Kunze
; Ruhr Universität Bochum, Institut für Experimentalphysik V, 44780 Bochum, Germany
Sažetak
The ultraviolet and visible spectra of plasmas produced by N2-laser radiation focused onto a copper target in air and in vacuum have been recorded photographically. The nitrogen laser beam (α = 337 nm) had a maximum energy density of 1.1 J/cm2, the pulse duration was 6 ns, and the repetition rate 0.2 Hz. The measured electron temperature was 15000 K (±30%) in air and 13000 K (±50%) in vacuum and the electron densities were 6.5×10^17 cm^-3 (±60%) and 3.0×10^17 cm^-3 (±60%), respectively. The irradiated surface in air and in vacuum was studied employing a metallographic microscope. In vacuum, the droplets were created and expulsed at the crater edges. Their formation is explained by the hydrodynamical model. They were formed in a time interval which is about two times shorter than the duration of the laser pulse. In air, droplets were also formed. The weight loss from the Cu-crater in vacuum was about 0.3×10^-4 μmole/pulse, in air it was about three times less.
Ključne riječi
laser-induced plasma; N2-laser radiation; short pulses; copper surface
Hrčak ID:
300890
URI
Datum izdavanja:
1.10.1998.
Posjeta: 483 *