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The temporal behavior of depolarization losses during the pumping and cooling phases in a flash lamp pumped Nd glass heat capacity disk laser is reported. We also investigated the influence of thermally induced birefringence on the laser performance by measuring the output energy and the deformation it produced in the probe beam. The complete two-dimensional thermal profile of the laser disk surface was measured for the determination of the thermal uniformity across the disk surface. A new concept for pumping the laser disk is proposed that can lead to a considerable reduction in the depolarization loss in the Brewster angle configuration and hence provide a high average power solid state laser with good beam quality. OCIS codes: 140.3580, 000.6850.

The thermal lens (TL) technique is employed to study the various thermal, as well as optical properties of several ion-doped phosphate glasses. Results prove that the temperature coefficient of the optical path length of the phosphates is smaller than the other systems.

The resistive transition broadening of the c-axis oriented La(sub (1.6-x))Nd(0.4)Sr(sub x)CuO4 epitaxial films are systematically investigated. It is found that the in-plane resistivity p (sub ab) below the mean-field transition temperature T (sub c)(H) follows Arrhenius-type thermally activated flux flow model.

High coercivity Nd-Fe-B films c-axis texture perpendicular to the film plane are prepared by dc magnetron sputtering and subsequent heat treatment. The influences of heat treatment and buffer layer materials on the microstructure and magnetic properties of the Nd-Fe-B films are investigated.

The nanocrystalline Pb(sub 0.92)Nd(sub 0.08)(Zr(sub 0.53)Ti(sub 0.47))(sub 0.98)O(sub 3)(PNZT) is synthesized by high-energy ball milling (mechanical alloying). The analysis of impedance and dielectric properties of PNZT as a function of temperature has showed the high permittivity of 10626 at 10 kHz at the Curie temperature (Tc), broadening of permittivity peak, lowering of Tc, decrease in conductivity and increase in relaxation time with the decrease in crystalline size.

The magnetization, thermal conductivity and thermopower of polycrystalline samples of [Nd.sub.1-x][Eu.sub.x]Ni[O.sub.3] compounds are measured as a function of temperature and external magnetic field. The results have shown a coexistence of ordered and disordered phases below the temperature [T.sub.N] and that an applied magnetic field is suitable for increasing the thermoelectric properties close to [T.sub.S].

The effects of the glass slag materials on the microstructures of the Nd-Fe-B alloys are examined. Coarse dendrites of alpha-Fe phase with grains of Nd2Fe14B were observed in Nd-Fe-B alloys on solidification of Nd-Fe-B melts in the molten lead silicate glass or in the molten soda-lime glass whereas columnar dendrite grains of Nd2Fe14B phase were observed in Nd-Fe-B alloys on solidification of the Nd-Fe-B melts in the molten Pyrex glass.

Several analyses are conducted to explain the synthesis and the structural, magnetic and thermal properties of the [Nd.sub.1-x][La,sup.x]Cr[O.sub.3] (0

Polycrystalline samples of [([La.sub.1-x][A.sub.x]).sub.0.67][Ba.sub.0.33][mn.sub.1.05][O.sub.3-[delta]] (with A being a mixture of lanthanides containing 66%La, 22%Nd, 8%Pr and 4%Ce) are prepared by the glycine-nitrate method. The results have shown that replacing lanthanum with a mixture of lanthanides is a good way to tune the working temperature of magnetocaloric manganites while maintaining a constant magnetocaloric effect.

Several analyses are conducted to explain the temperature driven metal-insulator transition taking place in the different epitaxial NdNi[O.sub.3] films. The results demonstrate that the observed transition is caused due to the occurrence of heterogeneous nucleation in the films.

The various effects of hydostatic pressure on the ferromagnetic phase transition and magnetocaloric properties of the [([Sm.sub.0.8][Nd.sub.0.2]).sub.0.52][Sr.sub.0.48]Mn[O.sub.3] single crystals are determined. The magnetization of the crystals is shown to increase considerably with the application of pressure.

Several studies are conducted to explain the structure, magnetic properties and the magnetocaloric effect observed in the various [Nd.sub.5][Si.sub.3] compounds. The compounds are shown to be extremely beneficial for a large number of magnetic refrigeration applications.

Several thermomagnetic analyses are conducted to explain the various magnetic properties, as well as the microstructure of the different directly quenched NdFeTiZrCrBC bulk magnets. A slight substitution of the C and Cr contents is shown to lead to significant enhancement of the properties.

Several analyses are conducted to explain the microstructural changes of the Nd-rich phases taking place in the Nd-Fe-B sintered magnet during the postsintering annealing process. The reduction in the lattice mismatch is shown to be the main factor that leads to an enhancement of the magnetic properties of the compounds.

The article presents a new approach, which employs the melt spinning and jet milling techniques for the preparation of high performance nanostructured Nd-Fe-B fine powders. The different effects of the jet milling conditions on the particle size and magnetic properties of these powders are also studied.

The impact of temperature on the spontaneous remagnetization observed in the various [Nd.sub.60][Fe.sub.30][Al.sub.10] and [Nd.sub.60][Fe.sub.20][Co.sub.10][Al.sub.10] bulk amorphous ferromagnets is discussed. The spontaneous remagnetization measure is shown to increase linearly with the temperature.

Several magnetic measurements and electron microprobe analyses are conducted to explain the microstructures, as well as the magnetic properties of the various sintered MR[E.sub.2][Fe.sub.14]B magnets (MRE = Y+Dy+Nd). Composition segregation of grains is shown to lead to the higher temperature coefficients in these magnets.

A study was conducted to examine NdMnSiH by magnetization and specific heat measurements. Findings highlight the magnetic properties, magnetic structures, and values of Nd and Mn ordered magnetic moments.

The temperature dependent thermoelectric power (TEP) studies has being carried out on [Nd.sub.0.67][Sr.sub.0.33]Mn[O.sub.3] nanocrystalline manganites to study the effect of nanosize on thermopower behavior of these manganites. Results result that magnon drag contribution predominantly contributes to the TEP in the ferromagnetic metallic (FMM) region.

The synthesis of [Nd.sub.25][Fe.sub.40][Co.sub.20][Al.sub.10][B.sub.5] by high-energy milling and melt-spinning techniques followed by subsequently annealed temperature range from 400 to 1100 degree Celsius for 20 min, is described. The findings from x-ray diffraction combined with high-resolution transmission microscopy for the annealed samples showed the presence of ferromagnetic [Nd.sub.2][(Fe,Co,Al).sub.14]B crystallites coexisting with antiferromagnetic [Nd.sub.6][(Fe,Co,Al).sub.14] ones, among an amorphous matrix.

Phosphorus diffusion and activation related phenomena in germanium is described and both conventional thermal processing and laser annealing is used by pulsed nanosecond Nd:YAG laser. A combined laser thermal treatment above the melting threshold prior to conventional annealing has allowed the elimination of the implantation damage in order to understand the impact of defects on both transient dopant diffusion and outdiffusion.

Magnetic and thermodynamic measurements for [R.sub.5]Ni[Pb.sub.3] (R=Ce, Nd, Gd) are described. Nonmagnetic [La.sub.5]Ni[Pb.sub.3] is used for isolating the magnetic heat capacity for all three materials and the results have included a relatively large linear-T term in the specific heat and integrated magnetic entropies consistently smaller than expected.

Neutron diffraction patterns are acquired in situ from a melt-spun amorphous [Fe.sub.74][Nd.sub.5][B.sub.18][Cr.sub.3] alloy upon rapid thermal annealing at constant rates. The heterogeneous nucleation of [Nd.sub.2][Fe.sub.14]B on tetragonal-[Fe.sub.3]B precipitates promoted by the 3d transition-metal additives is used for magnetic hardening.

The grain growth kinetics, as well as the effect of the sintering conditions and microstructural characteristics on the dielectric and electrical properties in [Nd.sup.3+] doped lead zirconate titanate (PLZT) (9/65/35) ceramics are examined at various temperatures. The ac conductivity analyses have followed the universal Jonscher law and the behavior of the frequency exponent is studied through the correlated barrier hopping model.

Conventional and anisotropic magnetocaloric effects are studied in cubic rare earth R[Ni.sub.2] (R = Nd, Gd, Tb) ferromagnetic intermetallic compounds. The crystalline electrical-field anisotropy is explored for predicting the anisotropic magnetotropic behavior and the results have shown the possibility of using both conventional and anisotropic magnetic entropy changes to extend the range of temperatures for use in the magnetocaloric effect.

The pressure dependence of the growth of [alpha]-Fe and [Nd.sub.2][Fe.sub.14]B nanocrystals in amorphous [Nd.sub.9][Fe.sub.85][B.sub.6] is measured. The studies have shown that the growth of nanocrystals is dependent on atomic diffusion mediated by vacancy-type thermal defects.

The synthesis of lanthanide coordination polymers from Pr(III), Nd(III), and Gd(III) salts and 2-hydroxynicotinic acid (Hnica) and MnS[O.sub.4].[H.sub.2]O under hydrothermal conditions is reported. The result from the variable-temperature magnetic susceptibility revealed ferromagnetic interaction between gadolinium(III) ions and antiferromagnetic interactions in Pr(III) and Nd(III) ions.

The observation of the pronounced polarization offsets in homogeneous [Bi.sub.3.15][Nd.sub.0.85][Ti.sub.3][O.sub.12] (BNdT) thin films sandwiched in Pt electrodes at elevated temperatures and high driving voltages has shown that the composition gradient is not required for the appearance of polarization offset. The strong temperature and voltage dependence has shown that the polarization offsets are related to thermionic charge injection, which is asymmetric to top and bottom electrodes.

Photo- and thermoluminescence (TL) spectra of NaLa[F.sup.4]:[Ln.sup.3+] (Ln = Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm) and NaLa[F.sub.4]:[Ce.sup.3+] (Ln = Nd, Sm, Ho, Er, Tm) are used together with the empirical Dorenbos model in order to establish the 4f energy level positions of all tri- and divalent lanthanide ions doped in NaLa[F.sub.4]. It is shown that the presence of two host related electron traps and the presence of [V.sub.k]-centers are required for describing the lanthanide-specific TL glow curves of both Ln mono- and Ce-Ln codoped NaLa[F.sub.4].

A study was conducted to explore the possibility of orienting [Nd.sub.2][Fe.sub.14]B solid particles in a nonmagnetic liquid phase under a magnetic field applied on a ribbon heated at a temperature above the melting temperature of the eutectic phase. The large temperature effect on the orientation behavior is attributed to the associated increase in the liquid phase volume fraction.

The thermal diffusion of neodymium ions was used for the confocal microspectroscopic characterization of planar optical waveguides fabricated in yttrium vanadate (YV[O.sub.4]) crystals. The results obtained from the analysis of spatial dependence of the [Nd.sup.3+] fluorescence provide insight into the spatial distribution of the fluorescence quenching and spectral shift and the mechanism responsible for the refractive-index modification and waveguide formation.

The solid state reaction method is used for preparing the complex perovskite system(1-x)La[(MgSn).sub.0.5][O.sub.3]-xNd[(MgSn).sub.0.5][O.sub.3] with the composition (x = 0-1). The dielectric constant has decreased and the temperature coefficient of resonant frequency has become less negative with the increase in neodymium concentration.

Magnetic, thermal and transport properties of NdNiPb and [Nd.sub.5]Ni[Pb.sub.3] and their crystalline electric field (CEF) splitting effects are examined. [Nd.sub.5]Ni[Pb.sub.3] has displayed a ferrimagnetic transition, whereas NdNiPb has displayed an antiferromagnetic phase transition associated with the alignment of crystal-field-split levels of the magnetic Nd ion and transport properties closer to those of a classic metallic system.

The structural, magnetic and magnetocaloric effect (MCE) of [La.sub.1-x][Nd.sub.x][Fe.sub.11.5][Al.sub.1.5] compounds are examined. The magnetocaloric effect has increased with Nd substitution and the refrigerant capacity is also large in Nd-substituted compounds, which is attributed to the tablelike MCE arising from the multiple transitions.

The ferromagnetism transition of [Nd.sub.1-x][Sr.sub.x]Mn[O.sub.3] compounds is examined by measuring magnetocaloric effect (MCE) and by applying a theoretical model based on Landau theory of phase transitions. The results have shown that the contributions to the free energy from the presence of correlated clusters have affected the MCE by coupling with the order parameter around the Curie temperature.

Electrical resistivity, heat capacity and dc magnetization measurements are performed on the Al[B.sub.2]-type intermetallics NdCuGe and LaCuGe over a wide temperature range. Simple-metallic behavior has provided a good fit to the NdCuGe thermopower and hence the CeCuGe results are attributed to resonant scattering due to partial hybridization of the localized orbitals.

Melt-spinning in the form of ribbons is used to prepare and study the magnetic properties of the [Nd.sub.49][Al.sub.13][Ni.sub.38] amorphous alloy. The findings from the hysteresis and temperature-dependent magnetization measurements provide insight into occurrence of a reentrant spin-glass behavior on cooling.

The magnetocaloric effect (MCE) is seen in three well-defined temperature intervals in polycrystalline [Nd.sub.0.5][Ca.sub.0.5]Mn[O.sub.3] (NCMO) manganite system displaying a first order (CO) transition. In the three given temperature regions, negligible magnetic and thermal hysteresis are observed, which has satisfied the requirements of using NCMO as an effective magnetocaloric material for magnetic refrigeration.

The fabrication of highly c-axis-oriented epitaxial Nb-doped SrO[(SrTi[O.sub.3]).sub.1] thin films is presented.

The synthesis, characterization, and the thermal properties of the mixed Nd:[Lu.sub.x][Gd.sub.1-x]V[O.sub.4] laser crystals are discussed. The observed mixed crystals are found to act as excellent laser materials and hence can be used in the Q-switched laser operation.

Two pulsed Ng-YAG lasers are used for measuring laser heating and ablation of graphite tiles of thermonuclear tokamaks. The theoretical models of laser heating and near-threshold ablation of graphite with imperfectly adhered layer are developed for interpreting the experimental results.

The anisotropic thermal lens (TL) effect is analyzed in [Nd.sup.3+] doped [Sr.sub.x][Ba.sub.1-x][Nb.sub.2][O.sub.6] crystals with two different stoichiometries. The results have shown a strong enhancement in the TL effect during the ferro-to-paraelectric phase transition and an inversion of the TL signal with the crystal stoichiometry.

The solidification of undercooled melts of [Nd.sub.x][Fe.sub.[100-1.5x]][B.sub.0.5x] (x = 10, 12 and 14) alloys is carried out in a drop tube and the changes of the microstructure and the phase constituent during the heat treatment of the as-doped sample are investigated as a function of sample diameter. The results have clarified the mechanism of the phase transformation in the rapidly solidified Nd-Fe-B alloys.

X-ray and neutron diffractions are used to perform the thermal expansion anomaly studies on Nd[(Fe, Mo).sub.12][N.sub.x] ( x=0, 0,5, 1) compounds. The analysis of the Neel curve and the system energy has shown that the anomaly is contributed to the strongly positive interactions.

An analysis of the glass-forming ability (GFA) of amorphous [Fe.sub.67][Co.sub.9.5][Nd.sub.3][Dy.sub.0.5][B.sub.20] is performed in terms of the width of the supercooled liquid region, the reduced glass transition temperature, the recently proposed parameter gamma, the Hruby parameter [K.sub.gl], and the stability parameter S. The value of the parameters obtained predict that the alloy has a good GFA, which can be cast in bulk form, whereas in reality the success of casting fully glassy specimen is limited to only 0.5 mm diameter rods.

The energy-transfer process and the related migration mechanism of excitation energy, important in the optical dynamics of Nd-doped glasses, were investigated. Efficient long-range migration of excitation energy of Nd(super 3+) ions was observed at 1.1wt% of Nd(sub 2)O(sub 3), the critical distance between Nd(super 3+) ions, shows that dipole-dipole interaction is not the dominant mechanism for energy transfer; the mean free path is the most probable mechanism for energy transfer.

The effects of phase distribution and grain size on the effective anisotropy and coercivity of the exchanged-coupled nanocomposite permanent materials was investigated. The dependence of coercivity on grain sizes is mainly determined by the effective anisotropy of the grains and the experimental enhancement of the coercivity with reducing grain size is attributed not to only the exchange-coupling interactions but also to the phase distribution.