Femtosecond laser pulse irradiation of Sb-rich AgInSbTe films: Scanning electron microscopy and atomic force microscopy investigations

The single-layer and multilayer Sb-rich AgInSbTe films were irradiated by a single femtosecond laser pulse with the duration of 120 fs. The morphological feature resulting from the laser irradiation have been investigated by scanning electron microscopy and atom force microscopy. For the single-layer film, the center of the irradiated spot is a dark depression and the border is a bright protrusion; however, for the multilayer film, the center morphology changes from a depression to a protrusion as the energy increases. The crystallization threshold fluence of the single-layer and the multilayer films is 46.36 mJ/cm(2), 63.74 mJ/cm(2), respectively.

Spectroscopic, and thermal studies of some new binuclear transition metal(II) complexes with hydrazone ligands containing acetoacetanilide and isoxazole

A new chelating ligand, 2-(2-(5-tert-butylisoxazol-3-yl)hydrazono)-N-(2,4-dimethylphenyl)-3-oxobutanamide (HL), and its four binuclear transition metal complexes, M-2(L)(2) (mu-OCH3)(2) [M = Ni(II), Co(II), Cu(II), Zn(II)], were synthesized using the procedure of diazotization, coupling and metallization. Their structures were postulated based on elemental analysis, H-1 NMR, MALDI-MS, FT-IR spectra and UV-vis electronic absorption spectra. Smooth films of these complexes on K9 glass substrates were prepared using the spin-coating method and their absorption properties were evaluated. The thermal properties of the metal(II) complexes were investigated by thermogravimetry (TG) and differential scanning calorimetry (DSC. Different thermodynamic and kinetic parameters namely activation energy (E

Super-resolution scanning laser microscopy with a third-order optical nonlinear thin film

In a configuration of optical far-field scanning microscopy, super-resolution achieved by inserting a third-order optical nonlinear thin film is demonstrated and analyzed in terms of the frequency response function. Without the thin film the microscopy is diffraction limited; thus, subwavelength features cannot be resolved. With the nonlinear thin film inserted, the resolution is dramatically improved and thus the microscopy resolves features significantly smaller than the smallest spacing allowed by the diffraction limit. A theoretical model is established and the device is analyzed for the frequency response function. The results show that the frequency response function exceeds the cutoff spatial frequency of the microscopy defined by the laser wavelength and the numerical aperture of the convergent lens. The main contribution to the improvement of the cutoff spatial frequency is from the phase change induced by the complex transmission of the nonlinear thin film. Experimental results are presented and are shown to be consistent with the results of theoretical simulations.

Efficient electronic implementations of adaptive systems for ambient intelligence environments

183 p.

Electronic properties of graphene grain boundaries

Grain boundaries and defect lines in graphene are intensively studied for their novel electronic and magnetic properties. However, there is not a complete comprehension of the appearance of localized states along these defects. Graphene grain boundaries are herein seen as the outcome of matching two semi-infinite graphene sheets with different edges. We classify the energy spectra of grain boundaries into three different types, directly related to the combination of the four basic classes of spectra of graphene edges. From the specific geometry of the grains, we are able to obtain the band structure and the number of localized states close to the Fermi energy. This provides a new understanding of states localized at grain boundaries, showing that they are derived from the edge states of graphene. Such knowledge is crucial for the ultimate tailoring of electronic and optoelectronic applications.