Infrared atomic Cs laser based on optical pumping of Cs2 molecules

Optical pumping of Cs2 molecules in a heat pipe with a pulsed dye laser around lambda = 476 nm yields laser action on the infrared atomic transitions 7S --> 6P at lambda = 1.47-mu-m and 5D --> 6P at lambda = 3.01-mu-m. From the measured dependences of spontaneous infrared fluorescence and laser output power on pump-laser wavelength and heat-pipe conditions (pressure and temperature), the different pumping mechanisms for the two atomic laser transitions could be clarified.