Design of Metal-clad Ti: LiNbO_3 Polarizer

ＤｅｓｉｇｎｏｆＭｅｔａｌ－ｃｌａｄＴｉ：ＬｉＮｂＯ＿３ＰｏｌａｒｉｚｅｒＨＵＨ．Ｚ．，ＣＨＥＮＧＧ．（ＤｅｐａｒｔｍｅｎｔｏｆａｐｐｌｉｅｄＰｙｓｉｃｓ，ＴｉａｎｊｉｎＵｎｉｖｅｒｓｉｔｙ，Ｔｉａｎｊｉｎ３０００７２，Ｃｈｉｎａ）ＧＥＮＦ；ＳＯＮＧ...     

Analysis of Fabrication Errors and Study of Calibration Method for Multilevel Diffractive Optical Element

ＡｎａｌｙｓｉｓｏｆＦａｂｒｉｃａｔｉｏｎＥｒｏｒｓａｎｄＳｔｕｄｙｏｆＣａｌｉｂｒａｔｉｏｎＭｅｔｈｏｄｆｏｒＭｕｌｔｉｌｅｖｅｌＤｉｆｒａｃｔｉｖｅＯｐｔｉｃａｌＥｌｅｍｅｎｔＦＵＹｏｎｇｑｉ（ＣｈａｎｇｃｈｕｎＩｎｓｔｉｔｕｔｅｏｆＯｐｔｉｃｓ...     

书评

书评ＡＩＰＨＡＮＤＢＯＯＫＯＦＣＯＮＤＥＮＳＥＲＭＩＣＲＯＰＨＯＮＥＳＴｈｅｏｒｘＣａｌｉｂｒａｔｉｏｎａｎｄＭｅａｓｕｒｅｍｅｎｔｓＧｅｅｒｇｅＳ．Ｋ．Ｗｏｎｇ，ＴＯｎｙＦ．Ｗ．Ｅｍｂｌｅｔｏｎ主编３２１＋ＸＶｌｌ页（ＡｍｅｒｉｃａｎＩｎｓｔｉｔｕ...     

Design and Characterization of Novel Comb Filters Based on Periodical Fiber Bragg Gratings

ＤｅｓｉｇｎａｎｄＣｈａｒａｃｔｅｒｉｚａｔｉｏｎｏｆＮｏｖｅｌＣｏｍｂＦｉｌｔｅｒｓＢａｓｅｄｏｎＰｅｒｉｏｄｉｃａｌＦｉｂｅｒＢｒａｇｇＧｒａｔｉｎｇｓＺＥＮＧＤｉｎｇｌｉＸＩＥＳｈｉｚｈｏｎｇＳＵＮＣｈｅｎｇｃｈｅｎｇＭＡＯＷｅｉｍｉｎｇＺＨＯ...     

Dye Laser-pumped Cr: LiSrAIF_6 Laser

ＤｙｅＬａｓｅｒ－ｐｕｍｐｅｄＣｒ：ＬｉＳｒＡＩＦ_６Ｌａｓｅｒ￥ＷＵＸｉｎｇ（Ｄｅｐｔ．ｏｆＰｒｅｃｉｓｉｏｎＩｎｓｔｒｕｍｅｎｔＥｎｇｉｎｅｅｒｉｎｇ，Ｔｉａｎｊｉｎ３０００７２，Ｃｈｉｎａ）Ｔ．Ｏｋａｄａ，Ｋ．Ｋａｅｄａ（Ｄｅｐｔ．ｏｆＥｌｅｃ?..     

Efficient Lasing Demonstration of a New Crystal Nd: Sr_5 (PO_4)_3F

Ｅｆｆｉｃｉｅｎｔ　Ｌａｓｉｎｇ　Ｄｅｍｏｎｓｔｒａｔｉｏｎ　ｏｆ　ａ　Ｎｅｗ　Ｃｒｙｓｔａｌ　Ｎｄ：Ｓｒ_５（ＰＯ_４）_３ＦＥｆｆｉｃｉｅｎｔＬａｓｉｎｇＤｅｍｏｎｓｔｒａｔｉｏｎｏｆａＮｅｗＣｒｙｓｔａｌＮｄ：Ｓｒ_５（ＰＯ_４）_３Ｆ￥ＺＨＡＯＳｈ...     

Operative Characteristics of the Dual-wavelength Cr: LiSAF Laser

ＯｐｅｒａｔｉｖｅＣｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆｔｈｅＤｕａｌ┐ｗａｖｅｌｅｎｇｔｈＣｒＬｉＳＡＦＬａｓｅｒＬＩＵＧｕｏｒｏｎｇＷＡＮＧＮｕｏＦＥＮＧＸｕａｎｑｉ（ＰｈｙｓｉｃｓＤｅｐａｒｔｍｅｎｔ，ＮｏｒｔｈｗｅｓｔＵｎｉｖｅｒｓｉｔｙ，Ｘｉ?..     

DEUTERIUM INFLUX PROFILE ALONG THE APEX OF THE UPPER X-POINT TILES IN JET

ＤＥＵＴＥＲＩＵＭＩＮＦＬＵＸＰＲＯＦＩＬＥＡＬＯＮＧＴＨＥＡＰＥＸＯＦＴＨＥＵＰＰＥＲＸ－ＰＯＩＮＴＴＩＬＥＳＩＮＪＥＴ￥Ｙ．Ｋ．Ｚｈｕ（ＳｏｕｔｈｗｅｓｔｅｒｎＩｎｓｔｉｔｕｔｅｏｆＰｈｙｓｉｃｓ，Ｐ．Ｏ．Ｂｏｘ４３２，Ｃｈｅｎｇｄｕ６１００４１...     

ELECTRON MOMENTUM SPECTRA OF EXCITED He(2~1S) AND He(2~3S)

ＥＬＥＣＴＲＯＮＭＯＭＥＮＴＵＭＳＰＥＣＴＲＡＯＦＥＸＣＩＴＥＤＨｅ（２１Ｓ）ＡＮＤＨｅ（２３Ｓ）ＣｈｅｎＺｈａｎｇｊｉｎＳｈｉＱｉｃｕｎＣｈｅｎＪｉＸｕＫｅｚｕｎＤｅｐａｒｔｍｅｎｔｏｆＭｏｄｅｒｎＰｈｙｓｉｃｓ，ＵｎｉｖｅｒｓｉｔｙｏｆＳｃｉｅｎ...     

An Experimental Study on the Output Properties of an Actively Mode-locked Er~(3 ) Doped Fiber Ring Laser

ＡｎＥｘｐｅｒｉｍｅｎｔａｌＳｔｕｄｙｏｎｔｈｅＯｕｔｐｕｔＰｒｏｐｅｒｔｉｅｓｏｆａｎＡｃｔｉｖｅｌｙＭｏｄｅ┐ｌｏｃｋｅｄＥｒ３＋ＤｏｐｅｄＦｉｂｅｒＲｉｎｇＬａｓｅｒＬＩＵＪｕｎＬＯＵＣａｉｙｕＺＨＯＮＧＳｈａｎＧＡＯＹｉｚｈｉ（Ｄｅｐａｒｔｍ...     

Pattern of the induced magnetic field in high-temperature superconducting ceramics

Our experiments performed earlier have shown that, when an external magnetic field is absent, the transport critical current in 3-d superconducting ceramics is a homogeneous function of the sample transverse sizes. The transport critical current density and magnetic field induced by the current are homogeneous functions of a point on the sample cross-section. Using these experimental results equations describing the induced magnetic field pattern in ceramic sample have been derived. The distributions of the transport critical current density and induced magnetic field in the samples having polygonal, diamond-shaped cross-sections illustrate the results.     

Effect of longitudinal applied magnetic field on the self-pinched critical current in intense electron beam diode

The effect of applied longitudinal magnetic field on the self-pinched critical current in the intense electron beam diode is discussed. The self-pinched critical current is derived and its validity is tested by numerical simulations. The results shows that an applied longitudinal magnetic field tends to increase the self-pinched critical current. Without the effect of anode plasma, the maximal diode current approximately equals the self-pinched critical current with the longitudinal magnetic field applied; when self-pinched occurs, the diode current approaches the self-pinched critical current.     

Creasing to cratering instability in polymers under ultrahigh electric fields

We report a new type of instability in a substrate-bonded elastic polymer subject to an ultrahigh electric field. Once the electric field reaches a critical value, the initially flat surface of the polymer locally folds against itself to form a pattern of creases. As the electric field further rises, the creases increase in size and decrease in density, and strikingly evolve into craters in the polymer. The critical field for the electrocreasing instability scales with the square root of the polymer's modulus. Linear stability analysis overestimates the critical field for the electrocreasing instability. A theoretical model has been developed to predict the critical field by comparing the potential energies in the creased and flat states. The theoretical prediction matches consistently with the experimental results.     

A new analytical model of high voltage silicon on insulator （SOI） thin film devices

A new analytical model of high voltage silicon on insulator (SOI) thin film devices is proposed, and a formula of silicon critical electric field is derived as a function of silicon film thickness by solving a 2D Poisson equation from an effective ionization rate, with a threshold energy taken into account for electron multiplying. Unlike a conventional silicon critical electric field that is constant and independent of silicon film thickness, the proposed silicon critical electric field increases sharply with silicon film thickness decreasing especially in the case of thin films, and can come to 141V/μm at a film thickness of 0.1μm which is much larger than the normal value of about 30V/μm. From the proposed formula of silicon critical electric field, the expressions of dielectric layer electric field and vertical breakdown voltage (V_B,V) are obtained. Based on the model, an ultra thin film can be used to enhance dielectric layer electric field and so increase vertical breakdown voltage for SOI devices because of its high silicon critical electric field, and with a dielectric layer thickness of 2μm the vertical breakdown voltages reach 852 and 300V for the silicon film thicknesses of 0.1 and 5μm, respectively. In addition, a relation between dielectric layer thickness and silicon film thickness is obtained, indicating a minimum vertical breakdown voltage that should be avoided when an SOI device is designed. 2D simulated results and some experimental results are in good agreement with analytical results.     

The critical magnetic field of anisotropic two-band magnetic superconductors

The upper and lower critical fields, and the critical field ratio of an anisotropic two-band magnetic superconductor in the Ginzburg–Landau (GL) scenario is derived analytically. The temperature-dependent upper critical field is investigated and applied to Fe-based superconductors. We find that a very high value of zero-temperature upper critical field in Fe-based superconductors can be found in the negative differential susceptibility region. The temperature-dependent upper critical field is presented in two formulas, in the empirical view and in the GL two-band view, which agrees with the experimental results.     

Calculation of critical states of superconducting multilayers based on numerical solution of the Ginzburg-Landau equations for superconducting plates

Numerical methods are used to analyze the Ginzburg-Landau equations for a superconducting plate carrying transport current in a magnetic field. Critical current is calculated as a function of the applied magnetic field strength for superconducting plates with different thicknesses. The relations between the field dependence of critical current and the distributions of order parameter, magnetic field, and supercurrent in a plate are analyzed. The field-dependent critical currents computed for plates are used to determine the critical current as a function of the applied magnetic field strength and local magnetic field and current distributions for multilayers in parallel magnetic fields. The constituent superconducting layers are assumed to interact only via magnetic field. A simple method is proposed for analyzing the critical states of multilayers in magnetic fields of arbitrary strength, based on elementary transformations of the critical current-density distribution over individual layers in zero applied magnetic field. The method can be used to analyze experimental results.     

Field effects and the critical end point in polymeric nematics

We calculate the effect of an external field on nematic polymer liquid crystals with polarizable dipoles along the chain backbone. In close analogy to conventional nematics we find a line of first-order transitions from nematic to paranematic as the field is increased, culminating in a critical end point as the critical field is attained. This critical point is related to those found by other authors. The results hold for electric and magnetic fields, the latter coupling to diamagnetic anisotropy. The electric case will be complicated if permanent dipoles are present. We demonstrate the equivalence of these results to the Landau approach in a field. Shortcomings in previous work on nematic polymers in fields are analysed.     

Quantitative test of SO(5) symmetry in the vortex state of Nd(1.85)Ce(0.15)CuO4

By numerically solving models with competing superconducting and antiferromagnetic orders, we study the magnetic field dependence of the antiferromagnetic moment in both the weak and strong field regimes. Through a comparison with the neutron scattering results of Kang et al. and Matsuura et al. on Nd(1.85)Ce(0.15)CuO4, we conclude that this system is close to a SO(5) symmetric critical point. We also make a quantitative prediction on increasing the upper critical field B(c2) and the superconducting transition temperature T(c) by applying an in-plane magnetic field.     

磁化等离子体中逃逸电子的临界速度

根据等离子体动力论,分析了在磁化等离子体中逃逸电子的临界速度,并在托卡马克参数下作了数值计算。计算表明,有磁场时,逃逸电子所受到的摩擦力,在纵向速度较大时比无磁场时的为大,这相应于逃逸电子临界速度的提高,因而高能的逃逸电子也较难产生。当磁场增大时,摩擦力略有减小。在纵向速度较高时,逃逸电子的横向速度分量对临界速度的影响较明显,横向速度越大,临界速度也越大。 关键词：     

Criticality of Epidemic Spreading in Mobile Individuals Mediated by Environment

We investigate the critical behaviour of an epidemical model in a diffusive population mediated by a static vector environment on a 2D network. It is found that this model presents a dynamical phase transition from disease-free state to endemic state with a finite population density. Finite-size and short-time dynamic scaling relations are used to determine the critical population density and the critical exponents characterizing the behaviour near the critical point. The results are compatible with the universality class of directed percolation coupled to a conserved diffusive field with equal diffusion constants.