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951.
N. V. Vysotina N. N. Rozanov V. E. Semenov V. A. Smirnov S. V. Fedorov D. N. Christodoulides 《Optics and Spectroscopy》2005,98(6):895-903
The polarization structure of nonparaxial spatial solitons in a transparent medium with the electronic mechanism of Kerr nonlinearity is studied theoretically. It is demonstrated analytically in the weak nonparaxiality approximation that the regime of polarization locking, in which all the field components have the same propagation constant, is the only stable regime. Estimates of the rate of transition of the initial metastable regime of rotation of the polarization ellipse to the regime of polarization locking are presented. Based on a numerical solution of the nonlinear Maxwell equations, the presence of the nonparaxial regime of polarization locking is confirmed and the main characteristics of the corresponding spatial solitons are obtained. 相似文献
952.
M. Tscherneck J. Kleinert C. Haimberger M. E. Holmes N. P. Bigelow 《Applied physics. B, Lasers and optics》2005,80(6):639-643
Ultracold molecules have been produced by photoassociation of Cs atoms trapped in a mirror magneto-optical trap. The molecules
were detected by resonantly enhanced multi-photon ionization followed by time-of-flight mass spectroscopy. The time-of-flight
ofatomic and molecular ions was investigated in the presence of a dc bias voltageapplied to the conducting mirror. This technique
provides a new tool for determining the distance between the cold molecules and the mirror surface.
This revised version was published online in August 2005 with a corrected cover date. 相似文献
953.
Q.-Y. Shao A.-D. Li J.-B. Cheng H.-Q. Ling D. Wu Z.-G. Liu N.-B. Ming C. Wang H.-W. Zhou B.-Y. Nguyen 《Applied Physics A: Materials Science & Processing》2005,81(6):1181-1185
LaAlO3 (LAO) gate dielectric films were deposited on Si substrates by low-pressure metalorganic chemical vapor deposition. The interfacial structure and composition distribution were investigated by high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), secondary-ion mass spectroscopy (SIMS), and Auger-electron spectroscopy (AES). HRTEM confirms that there exists an interfacial layer between LAO and Si in most samples. AES, SIMS, and XPS analyses indicate that the interfacial layer is compositionally graded La–Al silicate and the Al element is severely deficient close to the Si surface. Electrical properties of LAO films were evaluated. No evident difference in electrical properties between samples with and without native SiO2 layers was observed. The electrical properties are discussed in terms of LAO growth mechanisms, in relation to the interfacial structure. PACS 73.40.Qv; 81.15.Gh; 77.55.+f; 68.35.-p 相似文献
954.
D. Ohlberg J.J. Blackstock R. Ragan S. Kim R. Stanley Williams 《Applied Physics A: Materials Science & Processing》2005,80(6):1327-1334
A recently demonstrated [1] in-vacuo template-stripping process is applied to the study of platinum films stripped from ultra-flat silicon-oxide surfaces. Template-stripped (TS) Pt surfaces, prepared with a range of post-deposition annealing times prior to being stripped from the templating surface in an ultra-high vacuum (UHV) environment, are examined by UHV scanning tunneling microscopy (STM). These studies reveal that without post-deposition annealing, TS Pt surfaces are largely made up of poorly-ordered, granular nanostructures undesirable for many applications. The post-deposition annealing treatments explored in the study result in the emergence and continuous growth of large smooth crystallites. Issues with crystallite orientation relative to the TS surface and artefacts arising as a result of the epoxy used in the template-stripping process are presented and discussed in relation to optimizing the template-stripping procedure for specific applications such as self-assembled monolayer (SAM) formation for molecular electronics. PACS 68.37.Ef; 68.47.De; 68.55.Jk; 81.05.Bx; 81.15.Ef 相似文献
955.
The results of the elemental analysis of blood serum are often used for the diagnosis of different diseases associated with derangements of mineral metabolism. In this work, we studied the main sources of a systematic error in the atomic-emission spectrometric (AES) analysis of blood serum and developed a procedure for the AES determination of Ca, Cu, Fe, Mg, P, and Zn in the human blood serum. The repeatability relative standard deviations of determinations varied from 10 to 24%. 相似文献
956.
I. A. Anoshko V. S. Ermachenko L. E. Sandrigailo 《Journal of Applied Spectroscopy》2007,74(1):102-106
We present the results of a spectroscopic study of a nonequilibrium plasma in a Hall accelerator, in particular for such an
important parameter as the electron temperature. For the studied conditions, we used the semicoronal equilibrium model, which
relates the intensity ratios for two successive ionization steps for the same element.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 74, No. 1, pp. 93–96, January–February, 2007. 相似文献
957.
958.
959.
The phase transitions and phase state of hydroxypropylcellulose mixtures with ethanol and acetic acid under static conditions and in the shear field have been studied by the turbidity-point method and polarization microscopy with the use of a polarization-photoelectric setup and a modified plastoviscometer. The deformation of solutions leads to a decrease in the temperature of mesomorphic phase formation and to a change in the type of liquid crystals from cholesteric to nematic. 相似文献