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1.
A theoretical study of one-dimensional heterostructures composed of alternate layers of a Kerr polaritonic material and a linear dispersive metamaterial is performed. For frequency values at the edges of the non-Bragg zero-ϕeff gap of the heterostructure in the linear regime, a switching from very low to high transmission states is obtained and localized gap solitons of various orders are found, depending on the particular value of the incident power. Soliton solutions are shown to be robust with respect to absorption effects and a study is presented for gap soliton phases at the top and bottom of the zero-ϕeff gap in the case of defocusing and focusing nonlinearities. 相似文献
2.
Positive photoresists are widely used in lithographic process for the fabrication of relief components. When exposed to UV radiation they suffer chemical reactions modifying their chemical and physical properties. Aiming to follow molecular modifications among two different photoresists unexposed and previously exposed to ultraviolet light we have employed spectroscopic techniques coupled with mass spectrometry in the study of the AZ-1518 and AZ-4620 photoresists. The photon stimulated ion desorption (PSID) technique following the S K-edge NEXAFS spectrum was employed at the brazilian synchrotron light source (LNLS), during single-bunch operation and using time-of-flight mass spectrometry (TOF-MS) for ion analysis. NEXAFS and PSID mass spectra on both AZ-1518 and AZ-4620 photoresists (unexposed and exposed) were obtained and relative desorption ion yield curves determined for the main fragments as a function of the photon energy. They present marked different PSID spectra. Fragments related to the photochemical decomposition of the AZ-1518 photoresist could be clearly identified differently from the AZ-4620. Studies on the hardness of both photoresists were performed using O2 plasma reactive ion etching (RIE) technique, analyzed by scanning electron microscopy (SEM) and used to explain different desorption yields in the PSID spectra. These results show that the PSID technique is adequate to investigate structural changes in molecular level in different unexposed and exposed photoresists, which is crucial for improving our knowledge about the breakup process. 相似文献
3.
Impact of the sublinear photoconductivity law on the interpretation of holographic results in BaTiO3
R. A. Rupp A. Maillard J. Walter 《Applied Physics A: Materials Science & Processing》1989,49(3):259-268
Thick holographic refractive index gratings are written in nominally pure and in iron doped BaTiO3 crystals. The phase shift between refractive index grating and light pattern is studied as a function of an externally applied electric field by a direct phase shift measuring technique. The choice of the method is suggested by a theoretical analysis which allows for the effect of a nonlinear relation between photoconductivity and light intensity on the holographic writing process. 相似文献
4.
D. Brandl Ch. Schoppmann Ch. Tomaschko J. Markl H. Voit 《Applied Physics A: Materials Science & Processing》1994,58(6):557-562
Langmuir-Blodgett (LB) films of fatty acid salts (Y-stearate, Y-arachidate, Cu-arachidate, Ba-stearate) were thermally oxidized. As a result one obtains ultrathin (a few Å thick) metal-oxide films at the substrate. The surface of the metal-oxide films was found to be rather inhomogeneous. Y and Cu ions remain quantitatively at the substrate despite the heating procedure. A linear dependence between area density of the metal ions in the oxidized films and the number of monolayers of the LB films was observed. The preparation of a mixed metal-oxide film containing Y, Ba, Cu with a given stoichiometry was found to be difficult due to the effect of counter ion exchange. The samples were investigated by means of plasma-desorption and spontaneous-desorption mass spectrometry, by Rutherford back-scattering and electron microscopy. 相似文献
5.
V. Lyubin A. Arsh M. Klebanov M. Manevich J. Varshal R. Dror B. Sfez A. V. Latyshev D. A. Nasimov N. P. Eisenberg 《Applied Physics A: Materials Science & Processing》2009,97(1):109-114
The properties of non-linear inorganic chalcogenide photoresists fabricated by co-evaporation of Ag with amorphous arsenic
sulfide-selenide materials are considered in detail. The influence of several factors, including Ag concentration, irradiation
wavelength and composition of the developer on the photoresists characteristics was studied. Superlinear dissolution characteristics
of the photoresists are explained in the frame of the so-called “percolation approach”. The advantages of superlinear photoresists,
especially for the case of maskless photolithography, are briefly discussed. 相似文献
6.
Ar+ sputtering of an Cu(111) surface while simultaneously supplying Mo atoms is known to induce an oriented growth of Mo thin crystals, or seed-layers, on evolving conical Cu protrusions. The seed-layers thus formed are shown to be dual-oriented, or bicrystalline, consisting of columnar crystallites grown homo-epitaxially. The orientation relationship between the two types of crystallites was (100)I (111)II with [001]I [110]II, and this bicrystallinity probably resulted from a non-uniform charge-up of the layers' growth front. As concluded from high-resolution electron microscopy, the Mo(100) stacking is elastically converted into the Mo(111) stacking and vice versa, under the influence of tensile stress. The homo-epitaxy that the seed-layers exhibited is believed to reflect the mutual convertibility of the Mo(100) and (111) stackings. 相似文献
7.
Total ionizing dose effects of Si^+ ion implanted thermal oxides are studied by 10keV x-ray irradiation. Photoluminescence (PL) method is engaged to investigate nanostructures of samples. Ar^+ implanted samples are also studied by the same way to provide a comparison. The results show that Si^+ implantation following with high temperature annealing can significantly reduce the radiation induced flatband shift, which is caused by net posi- tive charge accumulation in oxides. This reduction is attributed to the formation of Si nanoscale structures. Ar^+ implantation is also found to reduce the radiation induced flatband shift, while it is different that the reduction with Si^+ implantation shows little dependence on implant dose of Ar^+ ions. This is explained by possible increase of recombination centres. 相似文献
8.
9.
By using the super-resolution near-field structure (super-RENS) method, the super-resolution recording marks are obtained practically by an organic photochromic diarylethene mask layer, under much lower recording laser power of 0.45roW. The size of recording marks is decreased by 60% (from 1.6μm to 0.7μm) for a diarylethene (photo-mode) recording layer by the optical detection method (limited by optical diffraction), or decreased by 97% (from 160Onto to 5Onto) for a heptaoxyl copper phthalocyanine (thermo-optical) recording layer, the latter is much smaller than the limitation of optical diffraction. In order to obtain a desirable result, a proper extent of photochemistry reaction in the mask layer is needed. Thus, the super-resolution recording marks can be obtained by adjusting the concentration of diarylethene in the mask layer, the recording laser power, and the moving speed of the sample disc. 相似文献
10.
F. Zappa S. Denifl I. Mähr J. Lecointre F. Rondino Olof Echt T. D. Märk P. Scheier 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,43(1-3):117-120
Embedding molecules in helium clusters has become a
powerful technique for the preparation of cold targets for spectroscopy
experiments, as well as for the assembly of complex, fragile molecular
species. We have recently developed a helium cluster source and a pick-up cell
to produce neutral beams of doped helium droplets, to be used as targets in
studies on electron collisions with molecules of biological relevance. In
the present work we present the results of a series of experiments on
electron-impact ionization of helium clusters doped with thymine and
1-methylthymine, where several interesting phenomena were observed, i.e.,
(i) electron impact ionization of molecular clusters inside the helium
droplets leads predominantly to protonated clusters; (ii) the appearance
energies are close to the ionization threshold of the helium atom but
ionization efficiency curves in addition extend down by several eV; (iii)
ionized molecular clusters can undergo metastable decay via the loss of one
neutral monomer. 相似文献