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The static and dynamic performance of high-speed Zn-diffusion vertical-cavity surface-emitting lasers (VCSELs) as affected by different Zn-diffusion depths is studied. The results have shown that the dynamic and static performance of high-speed VCSELs is optimized by controlling the Zn-diffusion depth and manipulating the number of optical nodes in the VCSEL cavity.

A study was conducted to experimentally investigate the two-dimensional expansion and the elliptical temperatures of several laser-induced plasmas (LIPs) produced during the ablation of metallic samples. A weak LIP, both in terms of temperature and in terms of forward peaking is observed to be associated with the ablation of Al, while a hot and dynamic LIP is produced during the ablation of a low boiling point material such as Zn with significant angular spread and high temperature.

Highly efficient (40-70% PL QY) and thermal ultrastable Mn: ZnSe d-dots are synthesized using greener approaches by nucleation-doping strategy. These stable d-dots have features of practical emissive materials, particularly for application with high power, high concentration of emitters, and under tough conditions.

The fabrication and photophysical characterization of a multichromophore array, [(Z3PN).sub.4]PDI, comprising of four zinc 5-phenyl-10,15,20-tri(n-pentyl)porphyrins(Z3PN) linked to the 1,7,N,N'-positions of perylene-3,4:9,10-bis(dicarboximide)(PDI) is described. The comparison of the two model compounds, N,N'-[(Z3PN).sub.2]PDI and 1,7-[(Z3PN).sub.2]PDI with the dynamics of energy and charge transport within the system is conducted.

The sensor platform of zinpyr 4 (ZP4) through pyrrole-for-pyridyl substitution is modified and the effects of this variation on both photophysical and metal-binding properties are evaluated. The utility of aniline-based ZP probes for select biological imaging applications are investigated.

In this paper, we describe the synthesis and characterization of analytical properties of fluorescence-based zinc ion-sensing glass slides and their application in monitoring zinc ion release from beta pancreatic cells in cell cultures. To fabricate the sensors, the zinc ion indicator ZnAF-2 {6-[N-[N',N'-bis(2-pyridinylmethyl)-2-aminoethyl]amino3', 6'-dihydroxyspiro[isobenzofuran-1(3H),9'-[9H]xan-thene]-3-one} was modified to include a sufficiently long linking aliphatic chain with a terminal carboxyl functional group. The recently synthesized ZnAF-2 zinc ion indicator provided high zinc ion selectivity in physiological solutions containing millimolar levels of calcium and other possible interfering cations. The carboxyl-modified ZnAF-2 was conjugated to the activated surface of glass slides, which then served as zinc ion sensors. It was possible to grow pancreatic cells directly on the zinc-sensing glass slide or on a membrane placed on these glass slides. The sensors were used to monitor zinc ion release events from glucose-stimulated pancreatic cells. The study showed that the zinc ion sensors responded effectively to the release of zinc ions from pancreatic cells at the nanomolar level with high selectivity and rapid subsecond response time.

The optical phonon frequencies of the wurtzite semiconductors GaN and ZnO are calculated as a function of angular variation with respect to the c-axis of these wurtzite crystals. In this article, it is shown that the interface phonon interaction potentials dominate the phonon interactions in both the heterostructures when the dimensions of the structures are small enough.

Mg(sub x)Zn(sub 1-x)O epitaxial composition spreads is fabricated, where the composition across the chip is linearly varied from ZnO to MgO. A unique growth relationship between cubic and hexagonal Mg(sub x)Zn(sub 1-x)O where their basal planes are coincident in the phase-separated region of the phase diagram where 0.37

A wide-range of Mn and Mg concentrations were used to grow molecular beam epitaxy of ternary alloy films. The wavelength dependence of the refractive indices for the alloy series was obtained.

An enhanced k-p optical calculation framework, based on the intracell interactions, is used to study the effects of bulk inversion asymmetry (tetrahedral) on the optical transitions of zinc blende semiconductor quantum wells. The study is found to be not very accurate for the calculations, as it does not reveal the variation in the optical transition strength of the complexes, which is mainly attributed to the inversion asymmetry of the substance.

Photoelectron spectroscopy is used for studying the BaCuChF (Ch = S,Se,Te) surfaces and BaCuChF interfaces with zinc phthalocyanine (ZnPc). Decapped BaCuSeF surfaces have remained O-free and C-free when the Se layer is evaporated but they have become F-deficient and in situ stepwise deposition of ZnPc on a BaCuSeF film surface has produced a chemically inert interface with a hole-injection barrier of 0.11 eV.

The studies of the polarization states of the localized sagittal modes in a solid/solid one-dimensional phononic crystal with a defect layer are presented. The existence of localized elastic modes in the band gaps and resonant vibrations inside the allowed bands as well as effect of change in polarization of some transmission peaks as function of the angle of incidence are also reported.

A newly developed amide-containing receptor for [Zn.sup.2+], combined with a naphthalimide fluorophore, termed ZTRS is presented. The developed ZTRS could be applied to image intracellular [Zn.sup.2+] ions in the presence of iron ions and to detect zinc ions during the development of living zebrafish embryos.

The in vivo optical imaging technique is employed to study the mammary, as well as the prostrate tumors in the living animals by using a synthetic near infrared zinc(II)-dipicolylamine probe. The approach is shown to be extremely effective, as the probe helps in targeting the necrotic regions of the tumors.

The carrier dynamics of donor-bound and free excitons, localized in the alloy disorder potential were examined for [Mg.sub.x][Zn.sub.1-x]O (0.08 [less than] x [less than] 0.33) thin films. The mean decay time of the excitons localized in the alloy disorder potential showed significant increase with increase in Mg content.

Zn-Zn porphyrin dimers are incorporated into thin dye-sensitized solar cells (DSSCs) to boost their light harvesting efficiency. The improved light harvesting ability coupled to enhanced DSSC performance has shown the potential of 3-D light harvesting arrays as next generation light harvesters for artificial solar energy conversion systems.

Several studies are conducted to explain the synthesis and the properties of a new novel gandolinium-based MRI zinc sensor. A new agent for the detection of free zinc ions with disrupting other biological processes is also identified and talked about.

The article studies effect of [Zn.sub.1-x][Mn.sub.x]Te light emitting devices under Curie-Weiss temperature. Findings suggest the presence of the acceptor bound magnetic polarons and their clusters in [Zn.sub.1-x][Mn.sub.x]Te crystals near the Curie-Weiss temperature.

A study was conducted to examine a strong photoluminescence band centered at 355 nm consisting of two emission peaks in 800 [degrees]C was observed in ZnTi[O.sub.3] thin film. Results suggested that emission peak at ultraviolet zone is resulted from [O.sub.2-] vacancy and that in the blue zone is attributed to [Zn.sub.2+] vacancy.

The mechanism by which dipicolylamine (DPA) chelate-appended fluorophores respond to zinc is examined by the preparation and analysis of five new analogues of the 2',7'-dichlorofluorescein-based [Zn.sup.2+] sensor Zinpyr-1 (ZP1). The results have shown that both binding pockets of the symmetric, ditopic sensor should be occupied in order achieve full fluorescence turn-on.

The tetracarboxylate organic linker and Zn(II) ions have assembled into chiral building blocks for a porous meal-organic framework with ferroelectric and second-order nonlinear optical properties.

An intramolecular charge transfer (ICT) fluorophore of smaller plane, 4-amino-7-nitro-2,1,3-benzoxadiazole, is adopted for constructing visible light excited fluorescent [Zn.sup.2+] sensor (NBD-TPEA). The studies have shown that NBD-TPEA staining is a reliable approach for the intact in vivo [Zn.sup.2+] imaging of zebrafish larva and also for clarifying subcellular distribution of [Zn.sup.2+] in vitro.

The electrical, optical and magnetic properties of Mn and Zn codoped Sn[O.sub.2] films displaying hysteretic ferromagnetism at room temperature are described. It is shown that the saturated magnetization of codoped Sn[O.sub.2] films have depended on the carrier concentration, which is consistent with the carrier-mediated model.

The effect of the cationic sites on the luminescent properties of [Eu.sup.3+] in [Gd.sub.2]BaZn[O.sub.5] is examined by the site-selective laser excitation and emission spectroscopy along with luminescence decays. The [Eu.sup.3+] ions have occupied two cationic sites and the Stark energy levels of [Eu.sup.3+] at two different sites in [Gd.sub.2]BaZn[O.sub.5] are assigned from selectively excited emission spectra at 10 K.

A near-field scanning optical microscope (NSOM) is used for performing structural and optical characterization of the surface layer after Zn diffusion in a channel waveguide fabricated on lithium niobate. An important part of the Zn at the upper layer surface above the channel waveguide is seen such as Zn[Nb.sub.2][O.sub.6] and ZnO nanocrystals having an average size close to 900 nm

A gamma-ray telescope mission concept based on Laue focusing methods is described. The studies have shown that a polarized beam has not changed its polarization level and direction after undergoing a small angle Laue diffraction inside a crystal.

The synthesis and characterization of a series of photochromic spirooxazine-containing zinc(II) diimine bis-thiolate complexes are reported. The results obtained provide insights into the photophysical and photochromic properties of the compounds and kinetic and thermal backward reaction and photochemical quantum yields for the photochromic reactions.

The coordination chemistry of four-coordinate zinc(II) and mercury(II) complexes of tetraarylazadipyrromethene ligands are describe. Semiempirical INDO/S computations have shown that these low-energy optical absorptions are derived from excitations among ligand-based orbitals that derive from the highest occupied molecular orbital and lowest unoccupied molecular orbital of the free azadipyrromethene.

The fluorescent chemosensors based on pyridylthioether macrocycles for metal ions are analyzed for their photophysical properties. The sensitivity of these two systems for zinc and cadmium ions is recorded.

A new avenue on the basis of metal complexation for the assembly of remote functionalized nonlinear optical (NLO) phores is explored to fabricate second harmonic generation (SHG) active materials. It is observed that the organization of remote functionalized molecules by metal ion complexation offers a convenient approach to the rational design of quadratic NLO materials.

ZnSe/95Si[O.sub.2]-5[B.sub.2][O.sub.3] nanocomposites are prepared by a sol-gel method and in situ growth technique. The average radius of ZnSe nanocrystals is about 2.5 nm and the band gap of the ZnSe/95Si[O.sub.2]-5[B.sub.2][O.sub.3] nanocomposites as estimated by extrapolating is about 2.95 eV.