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The high-pressure photoluminescence of the LiTaO 3 :Pr 3+ system obtained for the pressure range from ambient to 232 kbar at 20 K and ambient temperatures is presented. The observed pressure red shift of all spectral lines representing the f-f transitions is related to the changes in F 2 Racach integral and the spin-orbit coupling with pressure. To analyse the deexcitation kinetics and the dependence of the intensity of the 3 P 0 → 3 H 4 and 1 D 2 → 3 H 4 on the excitation wavelength and pressure we propose a model of a Pr 3+ trapped exciton with a hole localized at the Pr 3+ and an electron at the Rydberg states bounded by the long-range Coulomb potential of the hole.

We observed two ultrabroadband near-infrared (NIR) luminescence bands around 1.2 and 1.5 μm in as-grown bismuth-doped CsI halide crystals, without additional aftertreatment. Dependence of the NIR emission properties on the excitation wavelength and measurement temperature was studied. Two kinds of NIR active centers of subvalent bismuth and color centers were demonstrated to coexist in Bi:CsI crystal. The eye-safe 1.5 μm emission band with an FWHM of 140 nm and lifetime of 213 μs at room temperature makes Bi:CsI crystal promising in the applications of the ultrafast laser and ultrabroadband amplifier.

Work on optical properties of undoped and rare-earth doped YVO 4 crystals is briefly reviewed. Fundamental spectroscopic parameters relevant to laser performance of YVO 4 containing erbium, thulium and holmium, derived from absorption and emission spectra and from excited state relaxation dynamics, have been presented. Laser performance of YVO 4 :Er has been reported and laser potential of YVO 4 doped with thulium and holmium has been assessed. Anomalous phenomenon of up-conversion of IR radiation into red emission in YVO 4 :Yb,Ho and puzzling anti Stokes emission in nominally undoped YVO 4 have been discussed.

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