Lasing of a solution of coumarin 6 in the bleaching wave regime

The first liquid laser of a new type was constructed using ether solutions of coumarin 6 mixed with diphenylpolyenes. The laser was operated in the regime of a standing photobleaching wave with a lasing zone moving in the solution at a velocity comparable with that of sound (~1 km/sec). The excited region of 50 cm³ volume generated radiation of 2.5J energy for 15μsec in the green part of the spectrum (517±3 nm). It was found experimentally that lasing was quasicontinuous and steady, and that it could be scaled up in time and in volume. It was established experimentally that 1,4–diphenylbutadine and stilbene can quench effectively the triplet states of the molecules of coumarin 6 in ether solutions, which makes it possible to achieve prolonged lasing as a result of wide-band optical pumping.