Conveners
Magnetic Structures
- Romain Sibille (Paul Scherrer Institut)
- Martin Meven (RWTH Aachen University, Institute of Crystallography - Outstation at MLZ)
Hexaferrites are important metal oxides, widely used as both permanent magnets and microwave absorbers. Recently, hexaferrites have attracted great interest, because they show magnetoelectric effects at room temperature. [1,2]
We have synthesized W-hexaferrites with varied Co/Zn ratio and investigated the magnetic order using neutron powder diffraction. In SrCo2Fe16O27 and SrCoZnFe16O27 a...
Multiferroic Ba$_2$CoGe$_2$O$_7$ is well known for having an unconventional metal-ligand d-p hybridization mechanism responsible for the magnetically induced ferroelectricity [1,2]. It exhibits many exotic quantum phenomena, and among them anisotropic spin excitations and self-tunable single ion anisotropy under external applied magnetic field have been observed recently, using inelastic...
Analogous to electronic magnetism, a nuclear spin system can undergo a transition from a paramagnetic to a ferromagnetic or antiferromagnetic state subject to mutual dipole-dipole interactions. This exotic phenomenon, known as nuclear magnetic ordering (NMO), has only been observed in a few cases that form simple atomic single crystals. We recently developed a model to describe NMO in...
Chromium arsenide (CrAs) is considered a model system in which superconductivity and helimagnetism coexist. The superconductivity is induced by pressure and forms a dome-like phase region with a maximum TC of 2.2 K at about 1 GPa. The superconductivity occurs in the vicinity of an antiferromagnetical phase of CrAs which is incommensurate and described as a double helix in the literature. This...
We revisit the antiferromagnetic structure of $\rm Tb_{14}Ag_{51}$ with the propagation vector [1/3,1/3,0] and parent space group P6/m using both magnetic symmetry and irreducible representation arguments. We have found a new magnetic structure under the hexagonal Shubnikov magnetic space group P-6′, which fits much better the experimental data. This new solution was obtained by constraining...
