Spectroscopy and Laser Action of Anisotropic Single-Centered LiKYF5: Nd3+ Crystals Grown by the Hydrothermal Method

Spectroscopic investigations are made on new laser monoclinic single‐centered LiKYF5: Nd3+ crystals grown by the hydrothermal method. Stark levels of its activator ions for 37 2s+1 LJ manifolds lying up to ≈ 40000 cm−1 are established from luminescence and absorption spectra at 7 K. Using a new set of reduced‐matrix elements for electric‐dipole 4f3−4f3 transitions the intensity characteristics for LiKYF5: Nd3+ are calculated including phenomenological Judd‐Ofelt parmaeters Ω1, intermanifold absorption line strengths, as well as the radiative lifetime of the initial laser state 4F3/2 and branching ratios originated for its IR emitting channels. The kinetics of luminescence from four metastable states 2F(2)5/2, 4D3/2, 2P3/2, and 4F3/2 as function of Nd3+‐ion concentration and temperature are measured. Room‐temperture pulse, cw, and quasi‐cw stimulated emission of Nd3+ ions at two generating 4F3/2 → 4I11/2 and 4F3/2 → 4I13/2 channels under Xe‐flashlamp and laser‐diode pumpings are obtained. All observed induced inter‐Stark transitions are identified.