Complex metallic alloys: Electronic instabilities
Zusammenfassung der Projektergebnisse
Complex metallic alloys are poised at the border between the notions of conventional crystalline order, on the one hand, providing show-cases of generalized rigidities and symmetry breaking, and, on the other hand, quasi-crystalline, amorphous and glassy states that challenge these traditional concepts. The objective of this project has been exploratory work to identify the possible nature of electronic instabilities in CMAs. To address this goal, the project comprised of (i) a search for unusual electronic properties of quasi-crystals and CMAs, (ii) electronic (notably magnetic) order supporting complexities akin the structural properties of CMAs, but in conventional materials, (iii) technical advances to enable high resolution neutron diffraction and, in particular, spectroscopy under depolarizing conditions. The main results achieved in this project concerned the investigation of the magnetic and electronic properties of Mg11Ho15Zn74 quasi-crystals, the search for anomalous magnetic properties in µ-Al4(Mn,Cr) CMAs, the structure/magnetism relationship in Cs2CuCl4−xBrx single crystals, exploratory work on the structural and metallurgical properties of YMn2 and the crystalline character of the skyrmion lattice phase in MnSi. An important technical highlight of this project was the implementation and commissioning of a module that allows to perform neutron spin echo spectroscopy of depolarizing samples at a wide range of different neutron scattering instruments, thus enabling a search for intrinsic glassiness in CMA.
Projektbezogene Publikationen (Auswahl)
- Large scales – long times: adding high energy resolution to SANS. Nucl. Instruments and Methods in Physics Research A 654, 394 (2011)
G. Brandl, R. Georgii, W. Häußler, S. Mühlbauer, P. Böni
- Long-Range Crystalline Nature of the Skyrmion Lattice in MnSi. Phys. Rev. Lett. 107, 217206 (2011)
T. Adams, S. Mühlbauer, C. Pfleiderer, F. Jonietz, A. Bauer. A. Neubauer, R. Georgii, P. Böni, U. Keiderling, K. Everschor, M. Garst, A. Rosch
- Monte-Carlo simulations for the optimsation of a TOF-MIEZE instrument. Nucl. Instruments and Methods in Physics Research A 713, 71 (2011)
T. Weber, G. Brandl, R. Georgii, W. Häußler, S. Weichselbaumer, P. Böni
- Turn-key Module for Neutron Scattering with sub-µeV Resolution. Appl. Phys. Lett., 98, 073505 (2011)
R. Georgii, G. Brandl, N. Arend, W. Häußler, A. Tischendorf, C. Pfleiderer, P. Böni, J. Lal
- Low-temperature structural investigations of the frustrated quantum antiferromagnets Cs2Cu(Cl4−xBrx). Phys. Rev. B, 91, 035124 (2015)
N. van Well, K. Foyevtsova, S. Gottlieb-Schönmeyer, F. Ritter, R. S. Manna, B. Wolf, M. Meven, C. Pfleiderer, M. Lang, W. Assmus, R. Valenti, C. Krellner
- Neutron spin echo spectroscopy under 17 T magnetic field at RESEDA. EPJ Web of Conferences 83, 03008 (2015)
J. Kindervater, N. Martin, W. Häußler, M. Krautloher, C. Fuchs, S. Mühlbauer, J. A. Lim, E. Blackburn, P. Böni, C. Pfleiderer