Pumping iron: A KrF laser pumped atomic iron laser

A technique for producing stimulated emission in an optically pumped atomic iron system at room temperature is described. The required iron density (∼1014 atoms/cm3) for single pass amplified spontaneous emission was produced at room temperature by two techniques: a low pressure (50 torr) discharge of iron pentacarbonyl and neon and by the flash photodecomposition of Fe(CO)5 in an argon buffer. A commercial KrF laser producing output powers near 51 Mw was modified to improve the beam quality, and the beam was focused into the reaction cell. Resonant processes involving the 3d6 4p 4p (5F°) intermediate state of iron and the KrF laser field (λ?248 nm) produced stimulated emission near 300 and 304 nm in agreement with theoretical predictions.