UV-Cu II-laser with helical hollow cathodes

Abstract

UV lasing was obtained with helical copper hollow cathodes. The output powers have been measured multiline (248–270 nm) for some helix geometries as a function of different discharge currents, Ne pressures, and mirror reflectivities. A maximum laser power of 580 mW has been obtained in a segmented discharge tube with a total active length of 1.2 m. Laser action was also observed at 780 nm with a power of 1.3 W. The discharge stability is superior to other arrangements.

Erosion of helical cathodes for copper ion lasers

“…Discharge characteristics of the helical cathode show the transition from a hollow cathode discharge at small pitches to an ordinary glow discharge at large pitches where discharge occurs over the entire surface of the cathode [9]. In our experiment, uniform discharge was observed at the cathode surface.…”

An equivalent model of discharge instability in the discharge chamber of Kaufman ion thruster

“…A hollow cathode discharge is a unique gas discharge form seen in a cathode cavity. Owing to its high working pressure, high electronic density, and low maintenance voltage [1][2][3][4], it was first used as a spectral light source for high-resolution spectral analysis. Later, it was used in metal-vapor ion laser systems, electric propulsion, surface treatment, electrodynamic tether, and other applications [5][6][7][8][9].…”

High-gain ultraviolet Cu-II laser in a segmented hollow cathode discharge

“…The increased voltage hollow cathode discharges, such as the hollow-anode-cathode [6]- [8] and helical hollow cathode [9]- [12] discharges, provided higher stability and improved laser performance compared to the earlier constructions. The higher voltage of these discharges increased the ionization rate of the buffer gas and the sputtering rate because of the higher energy of positive ions bombarding the cathode surface, both features being advantageous for the efficient pumping of the metal ion lasers.…”