No abstract

ESR of Mo3+ ions and NMR of 27Al nuclei is investigated in mixed single crystals of yttrium-lutetium-aluminum garnets (Y1-zL~z)3A15012, where 0 5 xs 1. Several new centres of Mo3+ and 27Al compared with Y,Al,O,, and Lu3A150,, single crystals are revealed associated with symmetry and crystalline field parameter changes a t isomorphous substitution of Y3+ ions in therare-earth sublattice of the garnet by those of Lu3+. Symmetry, nearest coordination, and parameters of spin-Hamiltonians are estimated concerning all of M03+ and 27Al centres in (Y1-zLu,),Al,O1, at6~a p y x c e~ pf€n HOBblX, no CpaBHeHtiIo C Y3AI,01, II Lu3A1501,, UeHTPOB M03+ ti 27A1, 06yCJIOBJEHHbIX ti3MeHeHHFIMH CtiMMeTpMti ti IlapaMeTpOB HPtiCTaJIJIHYeCKOrO nOJIII npH ti3OMOp@HO~ 3aMeHe Y3+ Ha LU3+ B penK03eMenbHOi nOAPC!lueTK€! rpaHaTOB. YCTaHOBJleHbI CEIMMeTPHH, 6ntimafiluee OKpyWeHEie EI OIIpeHeJleHbl IIapaMeTpbI CnHH-FaMHJlbTOHIIaHOB BCeX UeHTPOB Mo3+ ti 27Al B KpacTannax (Y1-zLuJ3A1501, npti x < 0,15.

Yttrium aluminium perovskite YAlO3 (YAP) crystal, doped with rare-earth ions, has been extensively studied as a diode-pumped laser host material. The wide interest to rare-earth ions doped YAP crystals is explained by its good thermal and mechanical properties, high natural birefringence, widely used Czochralski  growth method. The aim of this work was to study the Yb3+:YAlO3  crystal as an active medium for high  power mode-locked laser.Yb3+-doped perovskite-like aluminate crystals have unique spectroscopic and thermooptical properties that allowed using these crystals as an active medium of high power continuous wave (CW) and modelocked (ML) bulk lasers with diode pumping.growth method. The aim of this work was to study the Yb3+:YAlO3  crystal as an active medium for high  power mode-locked laser.In our work spectroscopic properties of Yb:YAP crystal and laser characteristics in CW and ML regimes are investigated. Maximum output power of 4 W with optical-to-optical efficiency of 16.3 % and 140 fs pulse duration have been obtained for Yb:YAP E //c-polarization with 10 % output coupler transmittance. Tunability range as wide as 67 nm confirms high promise of using Yb:YAP crystal for lasers working in wide spectral range.