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Raman spectroscopic study of [Pb(sub 1-x)Ba(sub x)](Yb(sub 1/2)Ta(sub 1/2)]O3 ceramics, x = 0.0, 0.2, 0.25, 0.2, 0.3 and 1.0, combined with x-ray diffraction analysis and dielectric constant measurements are reported. The quantitative analysis shows that the substitution of Ba for Pb leads to a decrease in the degree of ordering and occurrence of local distortions in the lattice as seen by the broadening of certain peaks in the Raman spectra.

The defect chemistry of [Yb.sup.3+]:CaTi[O.sub.3] perovskite solid solutions is examined. Yb-doped CaTi[O.sub.3] ceramics are prepared by sintering and the dielectric properties of the final materials are measured as a function of temperature and frequency.

A high yield patterning techniques, involving the inducement of high voltage damage into the glass matrix is used to study and explain the patterning and periodic nanaostructuring of Er/Yb-codoped IOG1 phosphate glass by the Bragg reflectors. The ultraviolet laser-assisted method of selective chemical etching is being widely used to obtain deeper grating structures, which are commonly used in several waveguide laser devices.

The thermoluminscence (TL) of ytterbium oxide ([Yb.sub.2][O.sub.3])-doped zirconia (Zr[O.sub.2]) in response to ultraviolet (UV) and synchrotron x-ray excitations is examined. The results show that doping in Zr[O.sub.2] with the impurity ([Yb.sub.2][O.sub.3]) yielded strong TL peak at 105 degree Celsius and a weak TL peak at 205 degree Celsius and trapping centers associated with the TL peak at 150 degree Celsius.

The valency of Yb ion in YbIn[Au.sub.2] is determined by the Yb [L.sub.III]-edge x-ray absorption near edge structure spectroscopy at high pressure and the lattice compression curves of YbIn[Au.sub.2] and LuIn[Au.sub.2] compounds are observed by the x-ray diffraction measurement using intense synchrotron radiation x-ray sources. The results have shown that the valence state of Yb ion in YbIn[Au.sub.2] is strongly correlated to the unit-cell volume so that the magnetic 4[f.sup.13] state is stabilized at high pressure.

The spectroscopic characteristics of a high purity BaY2F8 (BaYF) single crystal doped with [Yb.sup.3+], which are grown by the Czochralski technique, are analyzed. The maximum temperature drop was found to be almost 4 K corresponding to a cooling efficiency of about 3%, but the limited tunability range of pumping source did not allow optimizing the cooling results.

The role of temperature on the up-conversion efficiency of materials that are good candidate to be used as the three primary-color emitters in optical written displays is discussed. A rate equation model is given for the blue emitting material that includes temperature-dependent coefficients for energy transfer and cross relaxation.

Magnetic measurements are performed on Yb3Fe(sub 5-x)O12(YbIG:Sc), x=0.5, single crystal platelets oriented along and perpendicular to the [111] crystallographic direction, in the 1.5-20 K temperature range in a magnetic field up to 330 kOe. It is found that the transition field, the linear H Yb-Fe variation domain and the saturation field are the same as along the [111] direction.

The temperature dependence of the Nd(super 3 +)Yb(super 3+) energy transfer rate in the YAL3(BO3)4 nonlinear laser crystal is investigated from the analysis of fluorescence decay curves recorded in the 10-600 K range. The populations of both Nd(super 3+) and Yb(super 3+) metastable states achieved after continuous-wave Nd(super 3+) excitation is calculated and measured and result is explained in terms of the thermal behavior of both forward and back transfer rates.

The dominant diffusing species in the formation of an amorphous interlayer between Yb thin films and crystalline Si substrates are determined by a Mo cluster marker experiment. The displacement of the Mo cluster marker in the amorphous interlayer during the Yb-Si interdiffusion indicates that Si atoms constitute the dominant diffusing species during the growth of amorphous interlayer.

The polycrystalline Yb(sub x)Ca(sub 1-x)MnO3 (x=0.1,0.2) were studied by x-ray powder diffraction, magnetic, and electrical resistivity measurements. The large asymmetry in magnetization and resistivity hysteresis loops is observed in this compound at 10 K, which might be due to the charge ordering and magnetocrystalline anisotropy.

The temperature and magnetic field dependencies of Faraday rotation (Fr) in the scandium-substituted ytterbium iron garnet Yb3Fe(sub 5-x)Sc(sub x)O12 (x=0.5) (YbIG:Sc) single crystal regarding the contribution from magnetic sublattices is investigated. The first-order electric dipole transition coefficient of the Yb(super 3+) ion is strongly temperature dependent as observed in pure YbIG, through the analysis of rare earth contribution to Fr.

The transient target surface phase transformations under CO2 laser irradiation, including both melting and vaporization, are seen and recorded for Y2O3 and Zn) by three different methods. Despite the differences in phase transformation, the agreements of the observed onset of melt and ablation in the two materials gave direct evidence for the physical mechanism operative in particulate removal under dual-laser ablation.

The experimental and theoretical investigation of thermally induced infrared-to-visible upconversion fluorescence emission enhancement in Yn3+/Pr3+ -doped fluorinated glasses excited at 1.064 Mum is examined. The model is based upon conventional rate equations considering the absorption cross sections of both sensitizers and acceptor as functions of the phonon population in the host matrix.