Metal‐free and asymmetric: The first enantioselective diamination of styrenes simply requires a chiral hypervalent iodine(III) reagent as an oxidant and bismesylimide as a nitrogen source (see scheme, Ms=methanesulfonyl). The reaction proceeds under mild conditions and with high enantiomeric excess.

The demonstration of Bose-Einstein condensation in atomic gases at micro-Kelvin temperatures is a striking landmark 1 while its evidence for semiconductor excitons 2-5 still is a longawaited milestone. This situation was not foreseen because excitons are light-mass boson-like particles with a condensation expected to occur around a few Kelvins 6, 7 . An explanation can be found in the underlying fermionic nature of excitons which rules their condensation 8 . Precisely, it was recently predicted that, at accessible experimental conditions, the exciton condensate shall be "gray" with a dominant dark part coherently coupled to a weak bright component through fermion exchanges 9 . This counter-intuitive quantum condensation, since

Room temperature photoluminescence at 1.6μm is demonstrated from InGaAs quantum dots capped with an 8nm GaAsSb quantum well. Results obtained from various sample structures are compared, including samples capped with GaAs. The observed redshift in GaAsSb capped samples is attributed to a type II band alignment and to a beneficial modification of growth kinetics during capping due to the presence of Sb. The sample structure is discussed on the basis of transmission electron microscopy results.

We report in situ and in real time quantitative measurements of stress along [110] and [110] directions during the formation of InAs/InP(001) quantum wires (QWr) and consequent stress relaxation. Results show a strong stress anisotropy due to the distortion of As-In bonds along [110] and As-As dimerization along [110]. This anisotropy is claimed to be the origin of QWr formation instead of self-assembled quantum dots. Anisotropic stress relaxation associated to QWr formation is shown to be characteristic of heteroepitaxial systems involving different group V elements grown by MBE under group V stabilized surface (2x4 reconstruction).

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