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The two-, three-, and four-level system terminology is used for describing lasers and are applied to many types of gain media, but are useful for comparing systems with discrete levels, pumped with a narrowband source, in near-resonance with the laser wavelength. Low-quantum-defect combinations of pump and laser wavelengths are studied for [Er.sup.3+], [Nd.sup.3+], [Yb.sup.3+] and [Ho.sup.3+] in YAG, as a function of temperature.

The operation characteristics of a KTA optical parametric oscillator (OPO) sin singly resonant oscillation mode using a multi-axial Q-switched Gaussian shape pump beam with grating having different grooves density is discussed to generate narrow-linewidth radiation. The examination has helped the technologies in developing tunable narrow-linewidth source in 3-5-[micro]m spectral range with desired energy and linewidth.

The sol-gel process is used for producing Nd-Mn-doped lead zirconate titanate (PZT) fibers. The measurements of the piezoelectric coefficient at superimposed electric field have proved the blocking of strain switching and the cyclation experiments with sesquipolar load has shown a pronounced linearity of the strain loops.

The basic elements of a 300 J/1 ns Nd:glass laser with high-efficiency frequency conversion are described, which have included a seed laser, a system shaping the spatial structure of the beam, a six-cascade amplifier based on neodymium phosphate glass rods and a second-harmonic generator on a DKDP crystal with ooe interaction. Reliable and easy operation has helped in the long-term functioning of the laser as a pump for the output cascade of a chirped pulse parameteric amplifier in a petawatt laser complex.

The efficiency for type-I second-harmonic (SH) generation in the biaxial nonlinear crystal Li[Bi.sub.3][O.sub.5] (LBO) is studied by considering the phase mismatching caused by Gaussian propagation inside a nonlinear crystal. LBO is used for achieving the generation of blue light by frequency doubling of a diode-pumped electro-optic Q-switched Nd:GSAG laser at room temperature and the maximum conversion efficiency for optimum focusing of the incident beam is shown to be 42%.

The possible causes of power limitation of nanosecond Nd:glass lasers are analyzed, where small-scale self-focusing is considered to be one of the main causes. A simple analytical dependence is found for an optimal distance between two nonlinear media and the maximum attainable energy in neodymium-phosphate glass lasers with rod amplifiers 10 cm in diameter is 400 J with pulse duration of 1 ns.

A low-pump-threshold, very high-repetition-rate, singly resonant optical parametric oscillator (OPO) pumped internally to a diode-pumped, Q-switched Nd : YV[O.sub.4] laser is described. The intracavity parametric cavity dumping process is used for achieving repetition rates in excess of 350 kHz while maintaining high down-conversion efficiency and have shown that the potential of the device in spectroscopic applications with an absorption measurement of low concentration C[H.sub.4].

The microwave dielectric properties of [Na.sub.x][Nd.sub.(2-x)/3]Ti[O.sub.3] solid solutions (x=0.05 to 0.5) were measured to study the effect of the compositional ordering in the A-sites of the perovskite structures characterized by 2 kinds of cations ([Na.sup.+], [Nd.sup.3+]) and vacancies. The results revealed that the quality factor (Q.f) of the [Na.sub.x][Nd.sub.(2-x)/3]Ti[O.sub.3] solid solutions depends on the compositional ordering in A-sites.

The development of the EM field in passively Q-switched Nd:YAG lasers is examined with the help of a computational model. Results suggest the formation of the second laser pulse and mode structure characteristic of higher order Laguerre-Gaussian beams.

The intracavity second harmonic generation in an actively Q-switched and mode-locked Nd:GdV[O.sub.4]-KTP green laser is discussed. Findings reveal that the repetition rate for the mode-locked green pulses was 476 MHz inside the actively Q-switched pulse envelope.

The effects of film thickness on the ferroelectric and dielectric properties are studied for the (Bi3.15Nd0.85)Ti3O12 (BNdT) films deposited on Pt/TiO2/Si(001) substrates by rf sputtering. The nonlinear dielectric behavior observed for BNdt films reveals occurrence of the domain wall pinning arising from the structural defects.

The interface development is investigated by high-energy electron diffraction (RHEED) and X-ray photoelectron spectroscopy (XPS) during the molecular beam epitaxial growth of Nd2O3 on Si(001). The XPS investigations reveals a large band offset above 1 eV with respect to silicon, indicating that the barrier heights for electrons and holes are quite high which makes Nd2O3 suitable for high-k application.

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.

Self-frequency doubling is obtained with the monoclinic biaxial bifunctional crystal: La2CaB10O19:Nd(super 3+). It is shown that two inequivalent Nd(super 3+) sites are able to operate self-frequency doubling under selective laser excitation.

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 effects of neodymium content and site occupancy on spontaneous polarization off epitaxial (110)(Bi(sub 4-x)Nd(sub x))Ti3O12 (x=0-0.73) films with a variety of neodymium content grown by metal-organic chemical-vapor deposition are investigated. The degraded spontaneous polarization might be associated with the site occupancy of the neodymium at the tow different kinds of bismuth sites.

The fabrication technique and electrical properties of basal plane tilted YBa2Cu3O(sub 7-x) (YBCO) superconducting bicrystal Josephson junctions are reported. Electrophysical and dynamic properties of the symmetric and asymmetric junction is studied and compared with ordinary ITJ junctions (In-Plane Tilted bicrytsal Josephon Junctions) on NGO substrates with the similar values of misorientation angles.

The presence of 1.2 mol % of Nd(super 3+) ions influences an effective deactivation process of the lowest excited states of Er(super 3+) and Ho(super 3+), decreasing the lifetime from 10 to 1 ms and from 17 to 2 ms, respectively, in Er: Nd: YLF and Ho:Nd: YLF crystals.

The results of the studies on the effect of rare earth neodymium (Nd) doping on the phase formation behavior and electrical properties of sol-gel derived Pb(sub 1.05)(Zr(sub 0.53)Ti(sub 0.47)O(sub 3) (PZT) thin films are presented. The perovskite phase is obtained up to 5 at. % doping and beyond that pyrochlore phase was found to coexist with the perovskite phase in all the films.

The compression shearing method is used for consolidating commercially available Nd-Fe-B melt-spun ribbons (MQ powders) at temperatures ranging from room temperature to 573 k. The bulk material consolidated at room temperature is magnetically isotropic, whereas the bulk material consolidated at 573 K is magnetically anisotropic.

The synthesis and characterization of near-infrared (NIR) emitting complexes of Nd(III), Er(III) and Yd(III) based on hexacoordinate lanthanide ions with an aryl functionalized imidodiphosphinate ligand, tpip, are described. The results indicate the effective shielding of the lanthanide by the twelve phenyl groups of the tpip ligands and the reduction of high-energy vibrations in close proximity to the lanthanide, which are the two important features in the design of NIR emitting lanthanide complexes.

A Q-switched oscillating Nd:glass laser is employed to analyze the characteristics of the near-infrared solid laser-induced blast waves. The occurrence of volumetric absorption in the near-infrared region of the waves is also demonstrated.

The various current-voltage characteristics exhibited by the stripe-ordered [La.sub.1.6-x][Nd.sub.0.4][Sr.sub.x]Cu[O.sub.4] bulk single crystals are analyzed. A significant increase in the critical current of the system is shown to lead to an extremely high jump in the voltage.

Several steady state and dynamic spectral studies are conducted to explain the characteristics of energy transfer exhibited by the (Nd, Yb):[Y.sub.3][Al.sub.5][O.sub.12] transparent ceramics. The Nd-Yb energy is shown to be highly dominated by the dipole-dipole interactions.

The effects of laser wavelength on the atomic, ionic and radiative emission from laser-produced tin plasmas are examined. Surface analysis of the craters created by the lasers have displayed that the mass ablation rate is higher for Nd:YAG laser generated plasmas when compared to C[O.sub.2] generated plasmas at maximum extreme ultraviolet (EUV) emission.

The microstructure and photoluminescence (PL) properties of Nd-doped Si[O.sub.2] thin films containing silicon nanoparticles (Si-np) are analyzed as function of the annealing temperature and the Nd concentration. PL excitation measurements have shown that the PL of [Nd.sup.3+] ions is nonresonant and has followed the excitation of Si-np giving new evidence of the energy transfer from Si-np toward the rare earth ions.

The magnetoelectric (ME) response and magnetic-field sensitivities of engineered laminate sensors comprised of magnetostrictive and piezoelectric phases are compared. The studies have resulted in the enhancement in the magnetic-field sensitivity for the structures with single crystals and the noise floors are lower for composites with Pb([Mn.sub.1/3][Nb.sub.2/3])[O.sub.3]-PbTi[O.sub.3] (PMN-PT) or Pb([Zn.sub.1/3][Nb.sub.2/3])[O.sub.3]-PbTi[O.sub.3] (PZN-PT) fibers than those with Pb(Zr,Ti)[O.sub.3] (PZT).