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We present a growth technique, which combines molecular beam epitaxy of ZnSe and externally wet‐chemically prepared, colloidal NCs of CdSe to achieve fully integrated monolithic epitaxial heterostructures. Our results show that wet‐chemically prepared semiconductor nanocrystals can be incorporated in an epitaxally grown crystalline cap layer. We investigated CdSe core, CdSe/ZnSe and CdSe/ZnS core/shell nanocrystals (NCs) overgrown with cap layers of ZnSe, where the thickness was varied between 20‐40 nm. In this paper we discuss PL measurements of overgrown NCs as a function of the cap layer thickness and compare the results with the PL of NCs in solution. A distinct blue shift of the PL is observed when the core/shell dots are overgrown by ZnSe. We present a model which explains this blue shift as resulting from dissolution of the shell of the dots during the overgrowth (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

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SummaryThe effect of the substitution of Fe by Co on the enhancement of glass-forming ability limits and subsequent nanocrystallization was studied in a rapidly quenched amorphous system (Fe x Co y ) 79 Mo 8 Cu 1 B 12 for y/x ranging from 0 to 1. The effect of Cu on nanocrystallization was investigated by comparison with Cu-free amorphous Fe 80 Mo 8 B 12 . Systems partially crystallized at the surface layer were prepared for y/x = 0 using different quenching conditions. The effect of heat treatment of master alloys used for ribbon casting was also assessed. The microstructure and surface/bulk crystallization effects were analysed using transmission electron microscopy and electron and X-ray diffraction in relation to the expected enhancement of high-temperature soft magnetic properties, drastically reduced grain sizes (∼5 nm) and Co content. Unusual surface phenomena were observed, indicating the origin of possible nucleation sites for preferential crystallization in samples with low Co content.