Efficient lasing near 1.4 μm in a (Cr, Ce, Nd):Gd3Ga5O12 crystal

The lasing and spectroscopic properties of (Cr Nd):Gd₃Ga₅O₁₂ [(Cr, Nd):GGG] and Nd:YAG crystals in the wavelength region 1.3–1.45 μm are compared. The cross sections for stimulated transitions of Nd³⁺ ions in this spectral region are found. Lasing at a wavelength of 1.4237 μm has been achieved in the (Cr, Ce, Nd):GGG crystal for the first time. An energy of 2.3 J in the light pulse has been achieved at an absolute efficiency of 1.2% during flash pumping of a free-running laser based on a (Cr, Ce, Nd):GGG crystal at this wavelength. An average laser output power of 21.6 W has been achieved at a pulse repetition frequency of 13 Hz. The advantages of (Cr, Nd):GGG crystals over Nd:YAG crystals for oscillation in the 1.4-μm region are discussed.