Atomic populations of copper and gold in a room-temperature metal vapor laser

• Published in: Journal of applied physics Vol. 66; no. 7; pp. 2794 - 2799
• Main Authors: ANDERS, A. K, TOBIN, R. C
• Format: Journal Article
• Language: English
• Published: Woodbury, NY American Institute of Physics 01.10.1989
• Subjects: 420300 - Engineering- Lasers- (-1989); ABSORPTION SPECTROSCOPY; COPPER; ELECTRIC DISCHARGES; ELEMENTS; ENERGY LEVELS; ENGINEERING; Exact sciences and technology; EXCITED STATES; FLUID FLOW; Fundamental areas of phenomenology (including applications); GAS FLOW; GAS LASERS; Gas lasers including excimer and metal-vapor lasers; GLOW DISCHARGES; GOLD; GROUND STATES; LASERS; MEDIUM TEMPERATURE; METAL VAPOR LASERS; METALS; METASTABLE STATES; OPERATION; Optics; Physics; PULSES; RESOLUTION; SPECTROSCOPY; SPUTTERING; TIME RESOLUTION; TIMING PROPERTIES; TRANSITION ELEMENTS; Gas laser; Gold; Vapor; Atoms; Population; Metal; Copper; Room temperature
• ISSN: 0021-8979; 1089-7550
• DOI: 10.1063/1.344206

Sputtering in the presence of a rapid flow of gas can project a column of metal vapor with a mean Cu i ground-state concentration along the optical axis of about 3×1014 cm−3. The effective gain length using a single cathode is limited to about 20 cm for both Cu i and Au i, due to the radial expansion of the metal vapor column. The laser has been studied for double pulsed operation during a single sputtering pulse. The ratio of the peak power for the second laser pulse to that of the first, ρ, increases with interpulse delay from zero at short delays to a constant value which is less than or equal to unity. The buildup of ρ occurs on a 700-μs time scale due to the residual ionization resulting from the first discharge pulse. The constant value decreases with increasing capacitor voltage for both the Cu i and Au i lines due to the radial flow of metal atoms from the optical cavity, which results from the transient heating of the metal vapor column.