Ultraviolet Ion Lasers

Abstract

We have extended cw laser action down to 220 nm. This represents a 100 nm improvement to the state-of-the-art prior to our work. Moreover, we have obtained cw laser oscillation on twenty additional transitions in the spectral region between 220 and 320 nm.

The successful laser systems, dominant laser transitions and maximum output power may be summarized as follows: Ne-Cu at 260 nm (350 mW); Ne-Ag at 318 nm (>350 mW) and He-Au at 280 nm (100 mW). It is noteworthy that ultraviolet laser threshold currents as low as 2 A have been observed. In comparison rare gas ion lasers require 20–50 A to reach threshold. Finally, the metals of interest are sputtered into the discharge allowing us to obtain metal densities of 10¹⁴ atoms/cm³ without the use of external ovens or discharge heating.

Our most recent attempts to scale the output power levels to one watt cw will be presented with particular emphasis on the 780 nm transition of Cu II.