Capture of carriers to screened charged centres and low temperature shallow impurity electric field break down in semiconductors

Free carrier capture by a screened Coulomb potential in semiconductors are considered. It is established that with decreasing screening radius the capture cross section decreases drastically, and it goes to zero when $$. On the basis of this result a new mechanism of shallow impurity electric field break down in semiconductors is suggested.Comment: 8 pages, latex, 1 figure in gif format, to be submitted to "Journal of Condensed Matter

Anisotropy and interaction effects of strongly strained SrIrO3 thin films

Magneto-transport properties of SrIrO$_3$ thin films epitaxially grown on SrTiO$_3$, using reactive RF sputtering, are investigated. A large anisotropy between the in-plane and the out-of-plane resistivities is found, as well as a signature of the substrate cubic to tetragonal transition. Both observations result from the structural distortion associated to the epitaxial strain. The low-temperature and field dependences of the Hall number are interpreted as due to the contribution of Coulomb interactions to weak localization, evidencing the strong correlations in this material. The introduction of a contribution from magnetic scatters, in the analysis of magnetoconductance in the weakly localized regime, is proposed as an alternative to an anomalously large temperature dependence of the Land\'{e} coefficient

Synthesis and Antibacterial Activity of N,N-Diethyl-3-substituted-2-(4-methyl-phenylsulfonamido)alkanamides and their Arylsulfonamide Precursors

A series of N,N-diethyl-3-substituted-2-(4-methylphenylsulfon amido)alkanamides (8a-k) and their arylsulfonamide precursors (7a-k) have been synthesized via facile approach. The chemical structures of the synthesized compounds were confirmed by analytical data and spectroscopic means. The in vitro antibacterial screening of these compounds along with streptomycin, showed N,N-diethyl-2-(4-methylphenylsulfonamido) -3-phenylpropanamide (8j) to be the most active agent on Escherichia coli at MIC of 12.5 μg/mL and on Staphylococcus aureus at MIC of 25 μg/mL