Searching for topological spin textures in a noncentrosymmetric antiferromagnet

The search for skyrmion-like topological spin textures (TST) in rare-earth based compounds has recently attracted much interest. We have grown both single crystal and polycrystalline samples of EuPtAs, which is an antiferromagnet crystallizing in a tetragonal polar structure. We have characterized the physical properties, and constructed the field-temperature phase diagrams, which show multiple field-induced phases. To solve the magnetic structures, and to search for potential TST in EuPtAs, we propose to measure powder neutron diffraction of EuPtAs in zero-field using the WISH diffractometer, so as to determine the zero-field magnetic structure. We also propose to measure single crystal neutron diffraction with magnetic fields applied along the c-axis, so as to map the evolution of the magnetism with field, and determine the magnetic structure in the field-induced phases.