Effect of the Coulomb blockade of Cooper pairs on the dynamic properties of small-size Josephson junctions

The dynamics of Cooper pair tunneling under Coulomb blockade in small-size Josephson junctions is studied in terms of the resistive model. A relationship between the delay time and temperature fluctuations of the Coulomb blockade edge and the rate of rise of the voltage across the junction is derived.     

离子型共聚单体参与下的全氟丙烯酸酯无皂乳液共聚

离子型共聚单体参与下的全氟丙烯酸酯无皂乳液共聚;全氟烷基丙烯酸酯;无皂乳液;离子型共聚单体     

A 1.107 μm Yb3+-doped Phosphate Fiber Laser Pumped by a Ti:sapphire

Lasers and amplifiers in a single fiber have been developed rapidly, especially for optical fiber communication and various sensors, in the recent years. However, remarkable progress and achievement have been made mainly in silica fiber doped with rare earth elements. In this paper, we report the progress on the development of the Yb3+-doped phosphate fiber laser.     

Effect of the anharmonic phase dependence of the supercurrent on <Emphasis Type="Italic">I-V</Emphasis> hysteresis in a Josephson junction

The effect of the anharmonic phase dependence of the supercurrent on I-V hysteresis in a Josephson junction is studied in terms of a modified resistive model.     

Hydrophobic/hydrophilic solvation: inferences from Monte Carlo simulations and experiments

In this study Monte Carlo simulations are used to determine the solvation properties of model hydrophobic (xenon and hard sphere) and hydrophilic (dimethyl ether) solutes in SPC/E water. Various contributions to the experimental solvation entropy, including the solvent reorganization entropy, have been determined. The main conclusion drawn, which is in accord with solubility data, is that poor solubility correlates with poor solute-water interaction. At room temperature, energy dominates the aqueous solubility of both hydrophobic and hydrophilic solutes, rather than entropy. However, at higher temperatures the solubility can pass through a minimum, and then entropy becomes dominant. Another interesting finding is the presence of larger than expected cavities in water. Two different simulation results support this finding. This unexpected hollow structure in water explains why a hard sphere solute is more soluble in water than in a comparable hard sphere or Lennard-Jones solvent. Hydrogen bonding causes water to aggregate into clusters that produce a few large cavities rather than many smaller cavities. The propensity for clustering also explains why water gives the illusion of being a low density liquid. Sufficient theoretical apparatus is developed to connect theoretical solvation properties to those measured by simulation and experiment. Finally, based on gas solubility, an intuitive hydrophobic/hydrophilic scale is developed.     

A molecular dynamics study of carbon dioxide in water: diffusion,structure and thermodynamics

Atomistic simulations are reported of a model of CO₂ in water. CO₂ is modelled by partial charges and Lennard-Jones interaction sites on each atom; the SPC/E model for water is used. Good agreement with experiment is found for the translational diffusion constants. The variation of the dynamics with the potential parameter was investigated. As expected, the orientational correlation times increase as the magnitude of the quadrupole moment is increased, but the translational diffusion constants are found to be surprisingly insensitive to the magnitude of the CO₂ quadrupole moment. The translational friction coefficient was resolved into electrostatic, Lennard-Jones and cross-terms; the Lennard-Jones contribution is found to be the largest. Varying the Lennard-Jones size parameter affects both translational and reorientational motion. In order to try to understand these results further, the variation of solvation free energy was investigated and the solvent structure around carbon dioxide was examined as the electrostatic and Lennard-Jones parameters were changed. The temperature dependence of the self-diffusion constant of pure SPC/E water was determined.     

Vortex lattice in LiFeAs superconductor in the two-band Ginzburg-Landau model

Time-dependent equations of the two-band Ginzburg-Landau model are simulated numerically. Calculations are performed for square thin films of the LiFeAs two-band superconductor in the vicinity of the superconducting transition temperature in the transverse magnetic field; the quasi-hexagonal nature of the vortex lattice in the intermediate state is demonstrated.     

Influence of the interplay between helicoidal magnetic ordering and superconductivity on the differential conductance in HoNi<Subscript>2</Subscript>B<Subscript>2</Subscript>C/Ag junctions

The point contact spectra of magnetic superconductor HoNi₂B₂C/Ag-based junctions is analysed in the framework of Blonder-Tinkham-Klapwijk (BTK) theory. The anomalous behavior in the dI/dV curves above the Neel temperature(T _N ∼ 5 K) is attempted to be explained by the partial suppression of superconducting gap parameter of the prevailing helical incommensurate structure     

Splitting of the energy level of a Josephson-junction qubit with an anharmonic current-phase relation

A Josephson-junction qubit with an anharmonic current-phase relation is studied. An analytical expression for the split of the ground energy level is derived.     

Numerical simulation of vortex nucleation in the two-band Ginzburg—Landau model

Technical Physics - Nonstationary equations are obtained in the two-band Ginzburg-Landau model. The nucleation of Abrikosov vortices in the intermediate state of a two-band superconductor is...