The compositional dependence of the electronic band structure has been computed for zinc blende ZnSxSe1−x and Zn1−xBexTe alloys with composition x ranging from 0 to 1. The empirical pseudo potential method with the virtual crystal approximation have been used. A particlar attention has been paid to the effect of alloy disorder on the electronic properties of the II-VI studied compounds. For this purpose, the compositional disorder is added to the virtual crystal approximation as an effective potential. Such correction approximates significantly our calculated values of the band gap bowing parameters to experimental ones. The ZnSxSe1−x gap energy shows a nonlinear behavior with strong bowing for low compositions of sulfur. The Zn1−xBexTe compound, as it is known, can be direct or indirect semiconductor depending on its beryllium composition x. The electron effective mass and the refractive index have been investigated as well. Polynomial approximations are obtained for both the energy gap and the effective mass as functions of alloy composition at Γ and X valleys.

Self‐assembed quantum dots (QDs) based on II‐VI compounds are interesting with regard to their electronic and optical properties due to their large scale provided by their fundamental gap. Among II‐VI materials, diluted magnetic semiconductor (DMS) nanostructures like CdSe/ZnMnSe and CdMnSe/ZnSe QDs are of particular interest due to the exchange interaction between the spin of the carriers and the spin of the paramagnetic Mn2+ ions located in ternary alloy layers. The application of an external magnetic field at low temperature induce the so‐called giant Zeemann effect of the band edges. In this work we first report the band offset calculations for zinc blende pseudomorphically strained CdSe/ZnSe interface. Then, we calculate the lowest electron states in both (Cd,Mn)Se/ZnSe and in CdSe/(Zn,Mn)Se QDs. Results show that the giant Zeeman splitting is more important when the Mn ions are inside the dot. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

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This paper examines the impact of the ECB’s monetary policy on corporate borrowing costs. We use an event study method to assess and compare the effects of both conventional and unconventional monetary policy on Germany and French corporate bond market (credit spreads). The sample of our research consists of daily data collected during the period from 04 January 1999 to 27 February 2015. This period spans the pre-crisis which begins when the ECB has launched the Economic and Monetary Union (EMU) and became responsible for the monetary policy in the euro area. We find significantly negative relation between conventional surprise and corporate credit spreads. Moreover, we find that a raise in German non-financial credit spreads and French credit spreads domestic in response to the SMP announcement. The OMT lowers the German non-financial credit spreads, while it raises German bank credit spreads and French corporate credit spreads both domestic and bund for two sectors. Finally, the LTROs are associated with a raise in corporate credit spreads. Our findings are confirmed in robustness checks by changing the non-standard monetary policy announcements with monetary policy event dummies used as one variable.