Effective 2.5-μm ZnSe:Cr2+ laser with transverse laser pumping

Effective lasing is obtained in the transversely pumped ZnSe single crystals that are doped with Cr 2+ ions using diffusion methods. A Q-switched Er 3+ -doped glass laser with a radiation wavelength of 1.54 μm is used for pumping. The resulting laser energy is 150 μJ at an absorbed pump energy of 600 μJ, so that the efficiency is 25% and the slope efficiency is 29%. An increase in the gain (up to the superluminescence level) due to the application of the transverse pumping of the active element with a substantially non-uniform distribution of the dopant is discussed.