Visible and ultraviolet lasers based on excimer transitions in the homonuclear halogens

Visible and ultraviolet lasers are based on excimer transitions in the diatomic homonuclear halogen molecules. Electron beam pumping of argon and hydrogen iodide gas mixtures produces a strong green emission in I2 centered at 505 nm and a full width of half maximum (FWHM) of the gain spectrum of approximately 15 nm. The transition for the green I2 band is bound-to-free, so a laser on this transition is continuously tunable. The result is a room temperature excimer laser that is potentially tunable over a region of 150A in the blue-green.