We study both theoretically and experimental1 the luminescence in non-intentionally but heavily p-doped GaAs quantum wells of 55 and 1501 width. At T=2K the PL spectra under cw excitation present an excitonic peak and a broad acceptor band. Time-resolved optical pumping of the acceptor line allows us to measure the free electron spin relaxation time. We have investigated its temperature depende...

All soil used anywhere in the world for agriculture contains radionuclides to a greater or lesser extent. Typical soils (IA89a) contain approximately 300 kBq/m3 of 40K to a depth of 20 cm. This radionuclide and others are then taken up by crops and transferred to food, leading to a concentration in food and feed of between 50 and 150 Bq/kg. The ingestion of radionuclides in food is one of the p...

We have measured independently both s-wave and p-wave cross-dimensional thermalization rates for ultracold 40K atoms held in a magnetic trap. These measurements reveal that this fermionic isotope has a large positive s-wave triplet scattering length in addition to a low temperature p-wave shape resonance. We have measured directly the p-wave threshold law which, combined with the Fermi statisti...

(BEDT-TTF)4Hg2.89Br8 (BEDT-TTF ) bisethylene dithiotetrathiofulvalene) is an ambient pressure low-temperature superconductor (Tc ) 4.3K) with an incommensurate two-sublattice structure. It crystallizes in orthorhombic and monoclinic modifications. Only the monoclinic phase becomes superconducting on cooling, as confirmed in this study. Its Hg sublattice undergoes a transition when the temperatu...

Graham Glass ([email protected]) CEO/Chief architect, The Mind Electric March 2001 This article describes the design and implementation of an intuitive, fast and compact (40K) Java toolkit for parsing and manipulating XML -Electric XML -the XML engine of the author's company. It shows one way to apply object-oriented techniques to the creation of an XML parser, and it provides useful ...

The ground state properties of CeCoPO, a homologue of the new high temperature superconductors LnFePnO1−xFx, were studied by means of susceptibility, specific heat, and resistivity measurements on polycrystals. The observation of a well defined Curie-Weiss behavior above 230K with μeff = 2.9μB and a ferromagnetic ordering below TC = 75K is similar to what was observed in LaCoPO and points to ma...

Activation of the phagocyte NADPH oxidase complex requires assembly of the cytosolic factors p47PHOX, p67PHOX, p40PHOX, and Rac with the membrane-bound cytochrome b558. We recently established a direct interaction between p67PHOX and cytochrome b558. In the present study, we show that removal of the C-terminal domain of p67PHOX increased its binding to cytochrome b558. Whereas phosphorylated p4...

Methods Starting point of the analysis is the Linear Non Threshold (LNT) assumption for radiation stochastic effect [1]: for effective doses (E) below 100 mSv, the probability of future stochastic damage is linearly related to E. This allows to add E from different sources to calculate a cumulative risk of health detriment. Data coming from literature were gathered to determine the average E de...

We report on the creation of ultracold heteronuclear molecules assembled from fermionic 40K and bosonic 87Rb atoms in a 3D optical lattice. Molecules are produced at a heteronuclear Feshbach resonance on both the attractive and the repulsive sides of the resonance. We precisely determine the binding energy of the heteronuclear molecules from rf spectroscopy across the Feshbach resonance. We cha...

In this paper we discuss results of MgB2 thin films deposition for the hot-electron bolometer (HEB) application. For this purpose a custom made hybrid physical-chemical vapour deposition (HPCVD) system was built. For films thicknesses d in the 15-45nm range the critical temperatures were from 34K to 40K. For bridges as narrow as 500nm the critical current density was >107A/cm2 indicating a high...