J. Stangl

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Indium tin oxide (ITO) nanopatterned electrodes are prepared from colloidal solutions as a material saving alternative to the industrial vapor phase deposition and top down processing. For that purpose highly monodisperse In(1-x)Sn(x) (x < 0.1) colloidal nanocrystals (NCs) are synthesized with accurate size and composition control. The outstanding(More)
Group III-V nanowires offer the exciting possibility of epitaxial growth on a wide variety of substrates, most importantly silicon. To ensure compatibility with Si technology, catalyst-free growth schemes are of particular relevance, to avoid impurities from the catalysts. While this type of growth is well-documented and some aspects are described, no(More)
III-V nanowires have been fabricated by metal-organic vapor-phase epitaxy without using Au or other metal particles as a catalyst. Instead, prior to growth, a thin SiOx layer is deposited on the substrates. Wires form on various III-V substrates as well as on Si. They are nontapered in thickness and exhibit a hexagonal cross-section. From high-resolution(More)
Silicon, arguably the most important technological semiconductor, is predicted to exhibit a range of new and interesting properties when grown in the hexagonal crystal structure. To obtain pure hexagonal silicon is a great challenge because it naturally crystallizes in the cubic structure. Here, we demonstrate the fabrication of pure and stable hexagonal(More)
Hard X-ray lens-less microscopy raises hopes for a non-invasive quantitative imaging, capable of achieving the extreme resolving power demands of nanoscience. However, a limit imposed by the partial coherence of third generation synchrotron sources restricts the sample size to the micrometer range. Recently, X-ray ptychography has been demonstrated as a(More)
A convenient, aqueous-based synthesis of stable HgTe nanocrystals with widely size-tunable room temperature emission between wavelengths of 1.2 to 3.7 mum is demonstrated. By the choice of the thiols, applied as stabilizers, we optimized the growth dynamics, the luminescence quantum yields (up to 40%), and a ligand-exchange procedure, required to transfer(More)
For three types of colloidal magnetic nanocrystals, we demonstrate that postsynthetic cation exchange enables tuning of the nanocrystal's magnetic properties and achieving characteristics not obtainable by conventional synthetic routes. While the cation exchange procedure, performed in solution phase approach, was restricted so far to chalcogenide based(More)
General algorithms to convert scattering data of linear and area detectors recorded in various scattering geometries to reciprocal space coordinates are presented. These algorithms work for any goniometer configuration including popular four-circle, six-circle and kappa goniometers. The use of commonly employed approximations is avoided and therefore the(More)
With the continued maturation of III-V nanowire research, expectations of material quality should be concomitantly raised. Ideally, III-V nanowires integrated on silicon should be entirely free of extended planar defects such as twins, stacking faults, or polytypism, position-controlled for convenient device processing, and gold-free for compatibility with(More)