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We investigate the Ne-like Cr x-ray laser at 28.6nm by using a modified 1D lagrangian hydrodynamic code MED103 coupled with an atomic physics data package and a 2D ray tracing code as a post-processor. The laser pumping configuration includes two prepulses and one main pulse. The first prepulse normally irradiates the target, while the second prepulse and the main pulse irradiate the target at grazing-incident angles. We predict that saturation can be achieved for the Ne-like Cr x-ray lasers with a total pumping energy of 125mJ. Good beam qualities with no deflecting angle and a small divergence angle of 5mrad are observed. [ABSTRACT FROM AUTHOR]

Ion-implantation layers are fabricated by multiple nitrogen ion-implantations (3 times for sample A and 4 times for sample B) into a p-type 4H-SiC epitaxial layer. The implantation depth profiles are calculated by using the Monte Carlo simulator TRIM. The fabrication process and the I-V and C-V characteristics of the lateral Ti/4H-SiC Schottky barrier diodes (SBDs) fabricated on these multiple box-like ion-implantation layers are presented in detail. Measurements of the reverse I-V characteristics demonstrate a low reverse current, which is good enough for many SiC-based devices such as SiC metal-semiconductor field-effect transistors (MESFETs), and SiC static induction transistors (SITs). The parameters of the diodes are extracted from the forward I-V and C-V characteristics. The values of ideality factor n of SBDs for samples A and B are 3.0 and 3.5 respectively, and the values of series resistance Rs are 11.9 and 1.0 kO respectively. The values of barrier height phB of Ti/4H-SiC are 0.95 and 0.72 eV obtained by the I-V method and 1.14 and 0.93 eV obtained by the C-V method for samples A and B respectively. The activation rates for the implanted nitrogen ions of samples A and B are 2% and 4% respectively extracted from C-V testing results. [ABSTRACT FROM AUTHOR]

The ohmic contacts of 4H-SiC are fabricated on nitrogen ion implanted layers made by performing box-like-profile implantation three and four times. Implantation parameters such as the standard deviation s and the projection range Rp are calculated by the Monte Carlo simulator TRIM. Ni/Cr ohmic contacts on Si-face 4H-SiC implantation layers are measured by transfer length methods (TLMs). The results show that the values of sheet resistance Rsh are 30 kO/# and 4.9 kO/D and the values of specific contact resistance rc of ohmic contacts are 7.1 x 10[?]4 O * cm2 and 9.5 x 10[?]5 O * cm2 for the implanted layers with implantation performed three and four times respectively. [ABSTRACT FROM AUTHOR]

The emission lines of B, C, O and Fe in tokamak plasma are reported. The spectra are compared with those calculated by the CHIANTI code, which is based on the collisional-radiative models with a large amount of accurate atomic data. General agreement is obtained between the results of experiment and computation. Most of the lines in the spectra are identified, and the relative number density ratios of B, C, O and Fe are determined. It is found that the processes of line formation in our experiment are similar to those in the stellar coronae. The line-averaged electron density of the tokamak plasma is measured by the HCN laser, indicating a good agreement with the theoretical prediction by the density-dependent line ratio of Fe XXI. [ABSTRACT FROM AUTHOR]

The Plankian radiation temperature of an intense x-ray source driven by imploding spherical CH plastic shell is measured with a filtered-multi-channel pinhole camera. With all the twelve laser beams of the GEKKO-XII laser facility applied, the average radiation temperature is measured to be around 465eV while the temperature at the core is as high as 818eV. This value is confirmed by other instruments applied. [ABSTRACT FROM AUTHOR]

From the theoretical analysis of the thermionic emission model of current-voltage characteristics, this paper extracts the parameters for the gate Schottky contact of two ion-implanted 4H-SiC metal-semiconductor field-effect transistors (sample A and sample B for three and four times multiple ion-implantation channel region respectively) fabricated in the experiment, including the ideality factor, the series resistance, the zero-field barrier height, the interface oxide capacitance, the interface state density distribution, the neutral level of interface states and the fixed space charge density. The methods to improve the interface of the ion-implanted Schottky contact are given at last. [ABSTRACT FROM AUTHOR]

Quasistatic magnetic fields generated by nonrelativistic intense linearly polarized (LP) and circularly polarized (CP) laser pulses in an initially uniform underdense plasma in the collision-dominated limit are investigated analytically. Using a selfconsistent analytical model, we perform a detailed derivation of quasistatic magnetic fields in the laser pulse envelope in the collision-dominated limit to obtain exact analytical expressions for magnetic fields and discuss the dependence of magnetic fields on laser and plasma parameters. Equations for quasistatic magnetic fields including both axial component Bz and the azimuthal one Bth are derived simultaneously from such a selfconsistent model. The dependence of quasistatic magnetic field on incident laser intensity, transverse focused radius of laser pulse, electron density and electron temperature is discussed. [ABSTRACT FROM AUTHOR]

A new band in the odd proton nucleus 123I is identified via in-beam g-ray spectroscopy using the 14N+116Cd reaction. This band shows up as doublets with the previously assigned pg7/2 [?] (nh11/2)2 band. Possible configurations of the new band are discussed in the framework of the cranked shell model and the geometrical model. It is argued that the new band might be a chiral partner of the previously known pg7/2 [?] (nh11/2) band. [ABSTRACT FROM AUTHOR]