Synthesis and crystal growth of new and well-established iron pnictide superconductors

• Applicant: Professor Dr. Bernd Büchner
• Subject Area: Experimental Condensed Matter Physics
• Term: from 2013 to 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 237720895

During this project, we will grow crystals with desired compositions and properties to address emergent questions in the field of iron pnictides. Our focus will be materials of the 1111, 122 and 111 pnictide family. We will grow new and emergent iron-pnictides where a reliable synthesis route guaranteeing high quality samples is yet unknown. During this project, we are aiming at the systematic exploration of the best suitable growth method (e.g. flux-growth, Bridgman technique) and optimal growth parameters (composition, temperature gradients ... ). At the same time, singleand polycrystals of well-established iron-pnictides will be provided to our collaboration partners as "samples on demand". For those samples, we already in full control of the growth parameters yielding high quality samples and hence, this part of the project is considered as a service to the SPP. We will use conventional solid state methods for the preparation of polycrystals of e.g. the 1111 iron-pnictides, and more sophisticated methods for the growth of single crystals. The growth methods range from growth using different types of flux to the Bridgman technique. All samples will be thoroughly characterised with respect to their structure, composition, magnetic, thermodynamic and transport properties. An important aspect of this project will be the systematic exploration and mapping of electronic phase diagrams as function of doping content.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1458: High Temperature Superconductivity in Iron Pnictides
• Participating Person: Dr. Sabine Wurmehl