Lasing in a medium with the properties of a Christiansen filter

Dye lasing in a dense slurry-like mixture, similar to the optical medium of the Christiansen filter, is first reported. A cuvette with lithium fluoride (LiF) crystal particles and an immersion liquid containing pyrromethene 567 dye was placed in a two plane mirror resonator and pumped by pulses of the second harmonic of the neodymium-doped yttrium aluminum garnet (Nd:YAG) laser. Twenty nanosecond pulses at 545-570 nm wavelengths with energies up to 0.6 mJ were obtained at the output of this slurry laser. The central part of the laser beam with a divergence of 6 mrad was usually accompanied by a ring structure of scattered radiation. The conditions of the generation development and formation of the output beam profile in a slurry laser as well as its possible applications are discussed.