Preparation and crystal growth of superconducting and magnetic rare earth-transition metal oxypnictides and alkali / earth alkali iron arsenides

• Antragsteller: Professor Dr. Bernd Büchner, seit 5/2010
• Fachliche Zuordnung: Experimentelle Physik der kondensierten Materie
• Förderung: Förderung von 2010 bis 2014
• Projektkennung: Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 168240948

We apply a systematic study aiming at understanding and optimizing the growth mechanism of iron pnictides and related materials. Our very broad spectrum crystal growth techniques will be used to achieve a general understanding of the essential growth parameters, to assess the potential of each technique for the different pnictide classes and to obtain large single crystals. Based on these results, we will synthesize materials optimized regarding structure, stoichiometry, and size, which will allow deducing the generic physical properties of these materials. To be specific, we apply growth from Snand self-flux, different Bridgman-growth techniques, and floating-zone growth under high Ar pressure. In addition, we will study in detail the role of defects and disorder based on well-defined materials. This work shall transfer our project BE1749/12 into the SPP 1458 and continue our work in which the set-up of a high pressure furnace was granted and where we successfully grew AFeAs (A = Li,Na), Co- and K-doped BFe2As2 (B = Ba,Ca,Sr) , and Fe(Se,Te) single crystals as well as high-quality REOFeAs-polycrystalline (RE = rare earth) doping series. All samples will be analyzed and characterized in detail by various techniques and the electronic phase diagrams will be investigated by means of structure, magnetic, transport, and thermodynamic studies. In addition, the samples will be provided to different groups in the priority program.

• DFG-Verfahren: Schwerpunktprogramme
• Teilprojekt zu: SPP 1458: Hochtemperatursupraleitung in Eisenpniktiden
• Beteiligte Person: Professor Dr. Rüdiger Klingeler
• Ehemaliger Antragsteller: Dr. Günther Behr, bis 5/2010 (†)