High-efficiency room-temperature ZnSe:Fe super(2+) laser with a high pulsed radiation energy

Characteristics of a ZnSe:Fe super(2+) laser operating at room temperature of active polycrystalline elements with large transversal dimensions are investigated. The active elements had a shape of plates with diameters D = 25-63 mm and width of ~4 mm, doped from two sides with iron ions by the diffusion method. The plates were doped in the process of hot isostatic pressing at an argon pressure of 100 MPa and temperature of 1250 degree C for 75-151 h. The laser was pumped by a non-chain electrodischarge HF laser operated in a single-pulse mode. The employment of active elements with greater transversal dimensions resulted in a suppressed transversal parasitic oscillation at large diameters of the pumping spot. The generation energy of 1.43 J with the slope efficiency eta sub(slope) = 53 % and the total efficiency with respect to the energy absorbed in an active element eta sub(abs) approximately 48 % was obtained on the sample of diameter D = 63 mm.