Polaron effects on the energy levels of hydrogenic impurities in GaAs/Ga1−xAlxAs quantum well structures

The effect of electron phonon-coupling on the binding energies of impurities in GaAs/Ga_1?χAl_χAs quantum well structures is calculated. The correction becomes sizeable as the electron gets more deeply bound.     

Deep impurity states in Hg1−xCdxTe

The chemical trends for the energy level of substitutional defects in narrow-band-gap semiconductor alloy Hg_1-xCd_xTe is studied. A minimal basis set in the empirical tight binding formalism is employed. The calculated trends seem to agree well with previous studies but there are some quantitative differences.     

Testing the durability of copper based preservative treated bamboos in ground-contact for six years

Cellulose - In this study, durability of bamboo samples in terms of the variability of location along culm height (top, middle and bottom) were evaluated in a ground-contact field test for six...     

Time-Domain Mapping of Electromagnetic Ray Movement Inside 2D Anisotropic Region

The paper presents the extension of the time-domain mapping method applied to 2D billiard problem inside an anisotropic region bounded by ellipse [1]. In this paper, it has been considered the ray movement inside 2D anisotropic region bounded by arbitrary differentiable curve. It has been proved that the problem can be one-to-one mapped onto 2D mathemeatical billiard problem inside the region possessing isotropic properties by linear transformation of group velocity hodograph and boundary with the same coefficient, which is equal to anisotropy of the ray group velocity, simultaneously. The main features of the ray movement inside 2D anistropic region are discussed.     

Shock-cavitational mechanism of X-ray generation during fast water stream cavitation

The process of generation of X-ray radiation formed during the free exit of a fast stream of water in a state of cavitation from a narrow channel was investigated both experimentally and theoretically. It was observed for the first time that the initial part of the stream and the outlet of the channel are the sources of intensive X-ray radiation (with an activity of 0.1 Cu), which is connected with the cavitation phenomena and the following excitation of shock waves. The frequency of the X-ray radiation depends on the composition of the radiating surface (water or the surface of the channel walls) and increases with the increase of the atomic number of the surface. The mechanism of radiation generation is connected with the influence of cavitation shock waves formed on the nearest interface (water-air, water-metal, metal-air, air-metal, etc.).     

Electronic properties of a large quantum dot at a finite temperature

The physical properties of a two-dimensional parabolic quantum dot composed of large number of interacting electrons are numerically determined by the Thomas–Fermi (TF) method at a finite temperature. Analytical solutions are given for zero temperature for comparative purposes. The exact solution of the TF equation is obtained for the non-interacting system at finite temperatures. The effect of the number of particles and temperature on the properties are investigated both for interacting and non-interacting cases. The results indicate that the effect of e–e interaction on the density profile shows different temperature dependencies above and below a certain temperature T_c.     

The electronic structure of In1−x Ga x P alloy by the recursion method

Summary The electronic structure calculation of In_1−x Ga _x P alloy using the recursion method is reported. A five-orbitals,sp ³ s ^*, per atom model is used in the tight-binding representation of the Hamiltonian. The local densities of states are calculated for In, Ga and P sites in a cluster of 216 atoms. The results are in reasonably good agreement with previous calculations. To speed up pubblication, the authors of this paper have agreed to not receive the proofs for correction.     

Lithium and antimony adsorbed on graphene studied by first-principles calculations

We have investigated the Sb and Sb₂ doping of graphene and the effect of Li_n (n = 2-4) atoms in detail. We find chemisorption only when we replace C with Sb and Sb₂ and distort the lattice. The additional adsorption of Li atoms changes the electronic band structure of the system.     

A continuum model for dephasing in mesoscopic systems

A model of continuous dephasing for one-dimensional mesoscopic conductors is proposed. The model is based on Büttiker's fictitious-probe model which is extended by attaching an infinite number of probes uniformly to various points on the conductor. The associated scattering problem is then solved. When the continuum limit is taken, it becomes possible to describe the dephasing as taking place everywhere. The dephasing rate enters into the model as an adjustable parameter. The effect of dephasing on the conductance for a double-barrier system is also studied numerically.