Nonlinear Dye Response under Nitrogen Laser Pumping

摘要

Nitrogen lasers have been used since many years to make dye solutions to lase. A nitrogen laser (337.1 nm) TEA at atmospheric pressure has been built in our laboratory. It has been characterized and used to pump cells of different sizes containing different dyes: Rhodamine 6G, Coumarin 440, DOTCI and pyranine. As a preliminary result it has been shown that pyranine can lase and this happens at very low threshold. Moreover, we have found that, independently on the dye concentration in the solvent the dyes under consideration can be grouped into two major classes of behavior: 1. Rhodamine 6G and DOTCI can lase both axially and transversally 2. Coumarin 440 and pyranine can lase only axially. Other intriguing features will be discussed and attention will be devoted to simultaneous multiple beam generation, superfluorescence and distributed axial pumping of dye solutions.