Abstract

Optically pumped molecular lasers using diatomic halogen gases have a long history dating to the first demonstration of a pulsed molecular iodine laser by Bycr et. al. in 1972.¹ Continuous-wave (cw) Raman lasing in molecular iodine (I₂) has been demonstrated with various pump lasers. Wellegehausen et. al.² pumped an I₂ Raman laser with a multi-watt argon ion laser. In this experiment, output powers of 250 mW were achieved in the mid infrared range of the spectrum, but the maximum photon conversion efficiencies (PCEs) were 14%. More recently, cw optically pumped I₂ Raman lasers have become of interest due to their large output wavelength spectrum.³⁻⁵ The PCE of all the cw systems has been limited to 14%. Dissociation and predissociation of the I₂, losses to spontaneous emission, and excessive intra-cavity losses are possible limiters of the PCE in earlier laser systems.^6,7 We present a 78% PCE I₂ Raman laser at 1300 nm. The high PCE is achieved by increasing the single pass gain, and minimizing the intra-cavity losses, allowing for higher circulating fields and more efficient output coupling of the laser radiation.

© 2002 Optical Society of America