Influence of the structure parameters on the gain and noise figure in silicon parametric amplifiers based on SOI Rib waveguides

Gain and Noise figure (NF) characteristics in dual-pump parametric amplifier based on silicon on insulator (SOI) Rib waveguides are numerically investigated in the presence of nonlinear losses. The impact of structure parameters of the silicon optical parametric amplifiers (SOPAs) on the gain and the NF are also analyzed. The results show that both the height and the width of the silicon on insulator (SOI) can affect the gain and the NF of SOPAs. 354 nm bandwidth (3 dB) and 8.135 maximum gain can be achieved by tailoring the structure parameters of the SOI rib waveguides. Moreover, the dispersion and the effective mode area of SOI are also analyzed.     

Near-infrared photonic crystals with higher-order bandgaps generated by two-photon photopolymerization

Three-dimensional photonic crystals with bandgaps of 1.5-2.3 mum in wavelength and with gap/midgap ratios of as much as 18% were generated efficiently by two-photon photopolymerization in a liquid resin. From 0.5-1.1-mW femtosecond-pulsed 540-nm light, woodpile structures consisting of 40 layers of elliptically shaped rods spaced at 350-500 nm were fabricated by focusing with a 1.3-N.A. objective. The high degree of correlation in these structures allowed the suppression of infrared transmission by as much as 50% as well as the observation of higher-order bandgaps. We also investigated the decrease in the gap wavelength on reduction of layer spacing, in-plane rod spacing, and rod size.     

DECONFINEMENT TRANSITION OF NONTOPOLOGICAL SOLITON MODEL AT FINITE TEMPERATURE

The temperatrure dependence of the σ_vac describing the extent of gluon condensation,and that of the color-dieletric constant K_vac describing the confinement of quarks,are discussed in nontopological soliton model at finite temperature; The mechanism of deconfinement transition is analysed.     

PRODUCTION OF LARGE-TRANSVERSE-MOMENTUM PHOTONS AND THE QCD PHASE TRANSITION IN ULTRARELATIVISTIC NUCLEAR COLLISIONS

The production of large-transverse-momentum photons from Quark-Gluon Plasma (QGP) is discussed,and is used to analyze the high multiplicity event found in the Japanese-American Cooperative Emulsion Experiment (JACCEE).The theoretical result turns out to fit the experiment well.Thus the production of large transverse momentum photons provides an experimental signal of the QCD phase transition.     

模糊推理的灵敏度

借助于模糊逻辑连接词的灵敏度,定义了模糊推理系统的灵敏度,研究了几种常见的模糊推理系统的灵敏度,进一步估算了各种模糊推理机的灵敏度,并将模糊推理系统的灵敏度与模糊连接词灵敏度的关系用等式表示出来。     

The Effect of the Electron-Phonon Interaction on Giant Magnetoresistance in Magnetic Multilayers

We built electron and phonon free energies and attempted to investigate the effect of the electron-phonon interaction on giant magnetoresistance in magnetic multilayers. Starting from a jellium-like model, we found that the electron-phonon interaction can have an important effect on the spin splitting of electronic energy band. The expression of giant magnetoresistance has been obtained by considering the spin splitting of electronic energy band,indicating that the effect of phonon could not be neglected. Numerical calculations using our approach demonstrate the agreement between experimental and theoretical values.     

1,5-苯并硫氮杂( )-β-内酰胺衍生物的 IR、MS、1H和13C NMR谱特征

本文测定并研究了两类1,5-苯并硫氮杂( )-β-内酰胺衍生物的红外光谱、质谱、核磁共振氢谱和碳谱,指出了主要谱峰的归属及此类化合物的谱学特征.     

On Connes’ trace formula for the Hankel transformation of order-1/2

A local Hankel transformation of order 1/2 is defined for every finite place of the field of rational numbers.Its inversion formula and the Plancherel type theorem are obtained.A Connes type trace formula is given for each local Hankel transformation of order 1/2.An S-local Connes type trace formula is derived for the S-local Hankel transformation of order 1/2.These formulas are generalizations of Connes’ corresponding trace formulas in 1999.     

The Dyson-Schwinger Method of the NJL Model Beyond the Mean Field Approximation

By making use of the generating functional method we derive the Dyson-Schwinger equations in the NJL model and obtain the revised quark gap equation due to the meson dressing effects (usually called beyond the mean-field correction), and finally analyze its influence on the meson properties as well as the nucleon sigma term.