The non-parabolicity, temperature dependence of an effective mass and scattering mechanisms in PbTe, PbSe, PbS are considered. The methods of investigation of non-parabolicity based upon measurement of thermoelectric power in strong magnetic fields and Nernst-Ettingshausen coefficient (together with other kinetic coefficients) are discussed. The results given by these methods are shown and disc...

We present a critical theoretical study of electronic properties of silicon nanoclusters, in particular the roles played by symmetry, relaxation, and hydrogen passivation on the the stability, the gap states and the energy gap of the system using the order-N [O(N)] non-orthogonal tight-binding molecular dynamics and the local analysis of electronic structure. We find that for an unrelaxed clust...

Measuring with a spectroscopic ellipsometer (SE) in the 1.845 eV photon energy region we determined the complex dielectric function (E = e1 + ieZ> of different kinds of amorphous silicon prepared by self-implantation and thermal relaxation (500 “C, 3 h) . These measurements show that the complex dielectric function (and thus the complex refractive index) of implanted a-Si (i-a-Si) differs from ...

graphite oxide constitutes carbon network with oxygen atoms both on hexagonal arrangement and the edge sites. structural and electronic properties for graphite-oxygen complexes have been explored using first-principles total-energy calculations within the local density approximation (lda). band structures and density of states for the propose carbon 3d models are reported. a finite energy gap and...

The wide-gap aluminothermic rail welds with root opening of 50-70 mm were produced using plain carbon steel rail and non-alloy aluminothermic charge. Mechanical properties and micro-structure of the weld metal and HAZ as well as the impact energy and the fracture toughness of the welds were investigated. The yield and tensile strength of wide-gap welds were about 98% and 95% of the base metal, ...