We develop the design method of luminescence device with the strained quantum dots (QDs) on Si using a theoretical analysis on realistic structure. We have calculated numerically the first electron and heavy‐hole quantum levels of self‐assembled InGaAsN/GaP QDs using the finite element method, the model‐solid theory and the band‐anticrossing model. The calculation results indicate that N incorporation into InGaAs QDs drastically reduces the conduction band minimum (∼120 meV/N at%), and that it is shown enough energy difference between the first electron‐quantum level and GaP X‐state when N composition is 1∼2%. For self‐assembled In0.5Ga0.5As0.99N0.01/GaP QDs, the calculated transition energy at room temperature (RT) nearly matches with the measured photoluminescence (PL) peak energy. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

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The authors have investigated the growth and luminescence properties of InPN alloys grown by solid-source molecular-beam epitaxy (MBE). The N composition increases with decreasing growth rate, P2∕In flux ratio, and growth temperature. In this work, the highest N composition obtained is 0.56% for the InPN sample. The appropriate growth temperature is around 400°C. However, the growth-temperature window of the InPN alloys having a smooth surface is very narrow. In order to obtain photoluminescence (PL) emission from the InPN samples grown by solid-source MBE, InPN alloys must be grown under the condition of lower-plasma power since the grown-in point defects induced by N plasma are reduced. Thermal treatment is effective to improve the luminescence efficiency of InPN alloys, and the appropriate annealing temperature is around 700°C. However, the S-shape behavior is observed only for the annealed InPN samples by atomic rearrangements during thermal treatment, which is attributed to the weaker bond strength of In–N than that of In–P. In addition, the PL peak energy corresponding to the near-band edge emission redshifts with increasing annealing temperature. These results indicate that the luminescence properties of InPN alloys are unique in contrast to other dilute nitrides such as GaAsN and GaPN alloys.

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Zwei Seelen wohnen, ach! in meiner Brust die eine will C‐H‐Aktivierung sich nennen, die andre frönet reduktiver Lust: Frei nach Goethe beschreibt dies die Umsetzung des Heterocyclus (CyNCH2)3 (Cy=Cyclohexyl) mit [SmIII(AlMe4)3]. Wie N. W. Mitzel et al. in der Zuschrift auf zeigen, werden C‐H‐Bindungen der Methylgruppen unter Bildung eines Carbinkomplexes mit {(HC)Al3Sm}‐Einheit aktiviert, und zudem tritt eine spontane Reduktion von Samarium(III) zu Samarium(II) durch die Methylgruppen auf.