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We study the recording of permanent Bragg gratings on surface-colored lithium fluoride (LiF) crystals by using the interference pattern of a continuous-wave UV argon-ion laser operating at 244 nm. Gratings with spatial periodicity ranging from 400 to 1000 nm are written by using a phase-mask interferometer and are stable for several months after the writing process. Absorption and photoluminescence spectra show the bleaching of primary F and F -aggregate laser-active color centers as a result of the process. Confocal microscopy is used to determine the pitch and the profile of the fluorescent gratings. The UV laser-induced optical bleaching in highly colored LiF ultrathin layers is responsible for the periodic spatial modulation of absorption and photoemission properties that characterize the gratings. In the colored surface layer, a reduction of as much as 50% of the initial color-center-induced refractive-index increase has been estimated in the bleached areas. OCIS codes: 050.2770, 140.3380, 140.1700, 230.4000.

We describe experimental results with a diode-pumped, passively Q-switched extracavity second- and third-harmonic generation. Cr:YAG is used as a saturable absorber for pulse generation. Taking into account the thermal effects of Nd:YAG at high incident pump power, we use a short plane-to-plane cavity configuration to take advantage of the maximum pump power and obtain the compactness structure. At the same time, we use the type-I critical phase-matched lithium triborate crystal to generate light at 532 nm and mix the residual fundamental at 1064 nm and the second-harmonic wave at 532 nm in the type-II critical phase-matched lithium triborate crystal for UV light generation at 355 nm. A third-harmonic-generation output power of 1.32 W is achieved at the incident pump power of 27.5 W, corresponding to an optical-to-optical efficiency of 4.8%. The instability of the UV laser power is less than 5% for 4 h. OCIS codes: 140.3480, 140.3540, 140.6810, 190.2620.

The polarization characteristics and intrinsic photoluminescence of M-plane GaN films on LiAl[O.sub.2] substrates were studied. The results have shown that the strain relaxation can occur in an anisotropic manner allowing for a maximum of the valence band splitting at a certain film thickness.

The synthesis of a lithium gadolinium phosphate crystal, Li[Gd.sub.5][P.sub.5][O.sub.13] was carried out by a high temperature solution reaction and solved by single-crystal X-ray diffraction data. Li[Gd.sub.5][P.sub.5][O.sub.13] presents a new structural type and is built up from [[Gd.sub.5][P.sub.2][O.sub.13]].sup.-] layers and one-dimensional Li chains with an unusual Li-Li distance.

The optical properties of lithium aluminum silicate (LAS) glasses doped with chromium ions are investigated. The infrared (IR) study of the glasses has revealed the presence of [Cr.sup.3+] ion, which has acted as network modifier.

A series of new lithium aluminum silicate (LAS) glass systems doped with chromium ion is prepared. The reflectance and transmittance of the glass slabs are recorded. By means of an iteration procedure, the glass refractive index n and the extinction coefficient k and their dispersions are obtained. Across a wide spectral range of 0.2-1.6 [micro]m, the dispersion curves are used to determine the atomic and quantum constants of the prepared glasses. These findings provide the average oscillator wavelength, the average oscillator strength, oscillator energy, dispersion energy, lattice energy, and material dispersion of the glass materials to be calculated. For optical waveguide applications, the wavelength for zero material dispersion is obtained. Dilatometric measurements are performed and the thermal expansion coefficient is calculated to throw some light on the thermo-optical properties of the present glasses correlating them with their structure and the presence of nonbridging oxygen ions. OCIS codes: 160.4670, 160.4760, 160.2750, 160.6990.

Self-assembled monolayers (SAMs) of 21-(16-mercaptohexadecan-1-oyl)-4,7,13,16-tetraoxa-1, 10,21-triazabicyclo[8.8.5]tricosane-19,23-dione were prepared on gold. Characterization of the SAMs was carried out by sessile drop contact angle, ellipsometry, grazing angle Fr-IR spectroscopy, and electrochemical techniques. The cation recognition properties of the SAM were studied by cyclic voltammetry and impedance spectroscopy. The films show moderate selectivity for detection of [Li.sup.+] ions in solution over [K.sup.+] and [Na.sup.+], with selectivity values calculated to be log [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII.] ~ -1.30 and log [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII.] ~ -0.92. To the best of our knowledge, this is the first demonstration of a lithium sensor fabricated using self-assembled monolayer technology.

The Eu (super 3+)-doped zinc oxyfluorotellurite (TZLFE) glass of molar composition 59TeO2-20ZnO-20LiF-1Eu2O3 are prepared and studied by broadband, Raman, and fluorescence-line narrowing (FLN) spectral techniques to investigate the local environment of Eu(super 3+) ion in this glass. The local structure of Eu(super 3+) ions in the TZLFE glass is almost similar to sodium borosilicate glass but with a shorter distribution of environments.

A gain amplifier for degenerated optical parametric chirped-pulse amplification (OPCPA) with lithium triborate and cesium lithium borate (CLBO) crystals was demonstrated in a near-collinear configuration. The signal gain of the final energy amplifier with CLBO was ~6. After compression, the 123 fs pulse duration was obtained. Compared with potassium dihydrogen phosphate, it is confirmed that CLBO is more effective as a nonlinear crystal in a final power amplifier for terawatt or petawatt OPCPA systems. To our knowledge, this is the first demonstration of OPCPA with CLBO. OCIS codes: 190.4970, 320.0320, 320.7090.

Thermo-optic properties of laser host materials are measured to enable solid-state laser performance modeling. The thermo-optic properties that are most commonly used for laser performance modeling are thermal conductivity kappa, coefficient of thermal expansion alpha, and thermal coefficient of the refractive index dn/dT.

In this paper we report on the optical and scintillation properties of [Cs.sub.2]LiY[Cl.sub.6] : [Ce.sup.3+] and [Cs.sub.2]LiY[Cl.sub.6] : [Pr.sup.3+] crystals. Crystals of Cs2LiYCIG doped with different [Ce.sup.3+] and [Pr.sup.3+] concentrations were grown and studied under optical, X-ray, gamma ray, and thermal neutron excitation. These scintillators ex1 hibit core-valence and self-trapped exciton luminescence in addition to fast emission from [Ce.sup.3+] and [Pr.sup.3+]. Efficient thermal neutron detection was observed for both scintillators. The position of the neutron peak in the pulse height spectra was found at about 5 times the channel number of the position of the [137.sup.Cs] 662 keV gamma peak. Index Terms--Cs2LiYCl6, scintillation detectors, scintillators, thermal neutron detection.

A series of novel borates, MM'(sub 4)(BO3)(sub 3) (M = Li, M' = Sr, M = Na, M' = Sr, Ba) are synthesized by standard solid-state reaction and their crystal structures are determined from powder X-ray diffraction data. The results are consistent with the crystallographic study and the differential thermal analysis (DTA) and TGA curves show that they are chemically stable and congruent melting compounds.

We present data on the lithium isotope compositions of glass reference materials from the United States Geological Survey (USGS) and the National Institute of Standards and Technology (NIST) determined by multicollector inductively coupled plasma mass spectrometry (MCICPMS), thermal ionization mass spectrometry (TIMS), and secondary ionization mass spectrometry (SIMS). Our data on the USGS basaltic glass standards agree within 2 [per thousand], independent of the sample matrix or Li concentration. For SIMS analysis, we propose use of the USGS glasses GSD-1G ([[sigma].sup.7] 31.14 [+ or -] 0.8 [per thousand], 2[sigma]) and BCR-2G ([[sigma].sup.7]Li 4.08 [+ or -] 1.0 [per thousand], 2[sigma]) as suitable standards that cover a wide range of Li isotope compositions. Lithium isotope measurements on the silica-rich NIST 600 glass series by MC-ICPMS and TIMS agree within 0.8 [per thousand], but SIMS analyses show systematic isotopic differences. Our results suggest that SIMS Li isotope analyses have a significant matrix bias in high-silica materials. Our data are intended to serve as a reference for both microanalytical and bulk analytical techniques and to improve comparisons between Li isotope data produced by different methodologies.

The comparison of short and ultrashort pulsed laser ablation in LiF is done. The hydrodynamic sputtering is much reduced by the use of short pulses and the femtosecond (fs) ablation is the preferred route to forming very thin LiF coatings.

The study obtained a complete description of the first hyperpolarizabilities of (HCN)n...Li and Li...(HCN)n (n=1,2,3). It indicates that these new alkali metal-molecular clusters have large nonlinear optical responses.

The study prepared Ni-V2O5.nH2) core-shell nanocable arrays for Li(super +) intercalation applications. Transmission electron microscopy (TEM) micrograph shows the Ni core was covered completely by a V2O5.nH2) shell.

Lithium-conducting nanocomposite polymer electrolytes based on high molecular weight poly(oxyethylene) are prepared from high aspect ration cellulosic whiskers and lithium imide LiTFSI salt. The thermomechanical behavior of the resulting films is investigated by differential scanning calorimetry, thermogravimetric analysis and dynamics mechanical analysis.

Single crystals of MgO were implanted with an energy of 175 keV Li (super +) ions at a fluence of 1multiplied by 10(super 17) ions/cm (super 2) was characterized by Rutherford backscattering and optical absorption measurements. It is observed that the hardening in the implanted region was primarily due to the extraordinary large concentration of both lithium and oxygen interstitials.

A novel experimental strategy that enables in situ Raman spectra of a single microparticle to be acquired while recording cyclic voltammograms at low scan rates, using LiMn2O4 in a Li(super +) - containing organic electrolyte as a model system is presented. Statistical analyis of the spectra obtained yielded results consistent with the information derived from XRD (X-ray diffraction) measurements making it possible to correlate optical data with phase composition for SOD (state of discharge) values in the range 11 and 35%.

The evaluation of the annealing process and effects for proton-exchanged LiTaO3 optical waveguides using the line-focus-beam ultrasonic material characterization system in a frequency range of 100 to 300 MHz is established. The leaky surface acoustic waves (LSAW) velocities decrease with an increase of the product fH, obtained from the frequency dependences and proton-diffused layer depths analyzed by secondary-ion mass spectrometry.

The surface condition of the electrodeposited lithium on nickel substrate is analyzed by tapping mode-atomic force microscopy (TMAFM) and surface potential microscopy (SPoM). The TMAFM presented the morphology of lithium deposits and the SPoM depicted the distribution of the surface condition on lithium deposits.

The study report on scintillation and luminescence characteristics of [Rb.sub.2]LiY[Br.sub.6] doped with 0.1%, 0.5%, 1%, and 5% [Ce.sup.3+] are presented. [Rb.sub.2]LiY[Br.sub.6]:0.5% [Ce.sup.3+] is observed to show very high thermal neutron scintillation light output of 83000 photons/neutron and could be used as an efficient scintillator for thermal neutron detection.

The stable and highly efficient organic light-emitting diodes (OLEDs) are demonstrated based on molybdenum oxide (Mo[O.sub.3]) as a buffer layer on indium tin oxide (ITO). It is found that the significant features of Mo[O.sub.3] as a buffer layer shows the low operational voltage with high electroluminescence (EL) efficiency and good stability in a wide range of Mo[O.sub.3] thickness.

A hybrid approach is described for the photoinscription of guiding channels in LiNb[O.sub.3] crystals, based on the combination of a traditional waveguide fabrication technology, such as proton exchange, with subsequent direct UV writing. The optical measurements have helped in identifying the optimum range of fabrication conditions for the production of well-guiding single-mode channel waveguides at telecommunications wavelengths.

Neutron diffraction with isotopic substitution was used to assess the relative solvation interaction near lithium ions in a D2O/deuterated poly(ethylene oxide) (PEO) mixed solvent near 25 degree Celsius. It was found that the presence of PEO in the aqueous solution has no effect on the hydration of Li (super +).

Several studies are conducted to explain the structural, as well as the optical properties of the different zirconium doped lithium niobate crystals. The Zr concentration of between 1.5 and 2 mol% is shown to lead to significant changes in the characteristics of the crystals.

Li doped NiO ([Li.sub.x][Ni.sub.1-x]O) thin films are epitaxially grown along [111] orientation on c-sapphire by pulsed laser deposition and their structural, electrical and optical properties of the films are examined. The insertion of i-MgZnO between the p and n layer has led to improved current-voltage characteristics due to reduced leakage current and the p-i-n heterojunction has displayed good rectification behavior with turn on voltage of 2.8 V and breakdown voltage of 8.0 V.

Ultrafast time-domain electro-optical characterization of the ballistic three-branch junctions (TBJs) is performed to examine their electrical response at terahertz (THz) frequencies. The analysis has disclosed poor coupling of the excitation signal into the rectifier because of a severe impedance mismatch between the rectifier and coplanar waveguide (CPW) as well as a parasitic capacitive coupling between the input and output ports of the rectifier.

A time-resolved luminescence spectroscopy technique was employed to measure the luminescence decays and to determine the most important mechanisms involved in the energy transfer up-conversion (ETU) processes that populate the [super 4][S.sub.3/2] and [super 4][I.sub.11/2] excited state. The results from the analysis of the ETU rate dependence on the wavelength and intensity of pulsed laser excitations allowed to obtain the ETU rate constants from the lower ([super4][I.sub.13/2]) and upper ([super 4][I.sub.11/2]) laser levels that could be used in the numerical solutions of the rate equation system for the Er-doped LiY[F.sub.4] (YLF) crystal.

The structural and optical properties of lithium tantalate (LiTa[O.sub.3]) powders doped with [Eu.sup.3+] ions are studied. The unit cell parameter a has presented the same behavior of the [Eu.sup.3+] occupation fraction in [Ta.sup.5+] sites as a function of the [Eu.sup.3+] content in LiTa[O.sub.3] and the same is seen for the variation in [Eu.sup.3+] occupation fraction in the [Li.sup.+] site and the unit cell parameter c with the [Eu.sup.3+] content.

The article reports several new quantum mechanical methods, which are used for the designing of a new type of lithium decarbohydrate, ] with a basketlike structure. The analysis has been shown to be extremely useful for the development of metal-boranes for NLO applications.

An efficient cathode material for organic light emitting diodes (OLEDs) consisting of a thin layer of the metal salt lithium phosphate ([Li.sub.3]P[O.sub.4]) deposited between the organic semiconductor and an Al cathode is described. The results obtained from [Li.sub.3]P[O.sub.4]/Al interface by Kelvin probe techniques offers insight into a work function lowering of the cathode that facilitated electron injection and the improvement in performance of respective organic light emitting diodes.

A third generation synchrotron facility is used for obtaining in situ, real-time, x-ray diffraction measurements in plate impact experiments. The synchrotron x-rays have provided real-time data regarding microstructure changes accompanying shock-induced deformation and structural changes in LiF crystals.

The synthesis and characterization of a new polar noncentrosymmetric material, [Li.sub.2]Ti[(I[O.sub.3]).sub.6], are described. The macroscopic polarity of [Li.sub.2]Ti[(I[O.sub.3]).sub.6] is attributed to parallel alignment of the stereoselective lone pairs on the [I.sup.5+] cations, which in turn has affected the material's second-harmonic generation, piezoelectricity and pyroelectricity.

Raman spectroscopy was used to determine standard enthalpy [Delta] [H.sup.o] and entropy [Delta] [S.sup.o] and evaluate the partial pressures and equilibrium constants for the reaction.from lithium amide and hydrogen to lithium hydride and ammonia at different temperatures. The measurements obtained from Raman intensity could be used to estimate ammonia partial pressures in gaseous products after heat and treatment of lithium amide under hydrogen atmosphere.

Optical absorption, spectrally resolved polarized upconversion fluorescence, and time-resolved luminescence spectra are used for examining the [Er.sup.3+] spectroscopic properties in a series of congruent LiNb[O.sub.3] crystals copoded with [Er.sup.3+] and MgO. The studies have shown that mild codoping with MgO has not facilitated the formation of clustered sites, whereas heavy codoping has facilitated it in [Er.sup.3+]-doped LiNb[O.sub.3] crystals.

The synthesis of new fluorinated lithium and ammonium sulfonimides by using the corresponding sulfonyl fluorides is described. The intermediates oxonium sulfonimides are neutralized and the obtained sulfonimides are shown to be potential electrolytes for lithium batteries or fuel cells.

The characteristics of the poling process of two samples of Er:LiNb[O.sub.3] grown by the Chzocralski technique is examined by comparing their optical properties. The results have that the erbium has caused a change of the coercive field value with respect to the pure congruent LiNb[O.sub.3] crystals and that the multidomain structure has affected the poling dynamics.

[Sm.sup.2+]-doped [Li.sub.2]O-SrO-[B.sub.2][O.sub.3] glass sample is prepared by the conventional melt quenching method in air atmosphere and [Sm.sup.2+] ions in this borate glass are obtained by x-ray irradiation reduction method. The microstructure of Sm ions in the [Li.sub.2]-SrO-[B.sub.2][O.sub.3] glass is examined and the microstructure is helpful in understanding the reduction mechanism of [Sm.sup.2+] ion in borate glasses.

The article presents a comparative analysis of the various damage features that are associated with the femtosecond pulse laser and swift-ion irradiations in lithium niobate (LiNb[O.sub.3]) crystals. The damages caused in both types of experiments are shown to increase with the irradiations.

The laser interferometry measurements are employed to study the changes taking place in the velocity correction and refractive index of the [100] lithium fluoride optical windows under shock compression, recompression and unloading conditions. The refractive index is shown to be highly dependent on the density of the compound.