Neutron scattering on emergent quantum materials

Topic  30
Main supervisor


MLZ institution FZJ
Local supervisor 1 Riccardo Brancaleon
Institution Promoscience
Local supervisor 2 Peter Boeni
Swiss Neutronics
Local supervisor 3 Christian Mammen
Institution JJ X-ray
Local supervisor 4 Rita Mezei
Institution Mirrotron
Title Neutron scattering on emergent quantum materials
Description Recent theoretical predictions and experimental realizations of exotic quasi-particles and topological excitations in condensed matter, such as Dirac and Weyl fermions in topological semimetals and magnetic monopoles in spin ice, have led to tremendous research interests in emergent quantum materials. As a unique microscopic probe, neutron scattering is ideally suited for the studies of static and dynamic magnetic correlations in these materials. This can be demonstrated by the recent work carried out in the group led by the main supervisor at MLZ [1-8].
The overarching theme of the proposed topic is to use advanced neutron scattering techniques, including time-of-flight neutron diffraction, longitudinal and spherical neutron polarisation analysis and inelastic neutron scattering, to investigate magnetic order and collective excitations in emergent quantum materials, such as magnetic kagome semimetals, kagome superconductors, quantum spin ice, quantum spin liquid and Kitaev materials etc., with the aim to elucidate the fascinating interplay between topology, electronic correlation and magnetic frustration. High-quality single crystals of various quantum materials have been successfully grown in the group, which can be naturally used for this topic. Given the recently commissioned time-of-flight inelastic neutron scattering (TOF-INS) option at the polarized instrument DNS [9], one interesting prospect is to fully exploit the tremendous potential on the studies of quantum materials by combining TOF-INS and wide-angle polarisation analysis (WAPA), and to be actively involved in the new instrument upgrade project DNS-WAPA. Another interesting prospect is to be involved in the inelastic and polarised diffuse neutron scattering data analysis using advanced numerical approaches and modern software in a close collaboration with the leading theory groups [4-5].
We therefore seek highly motivated young researchers to work on the individually tailor-made projects in this topic, which, depending on the interests and research background of candidate, could be oriented more towards either materials synthesis, or neutron scattering experiment and data analysis, or neutron method and instrumentation development. In addition to the on-site research at MLZ, frequent travels for beamtime at other neutron facilities, e.g., ILL, ISIS, PSI, J-Parc, ANSTO and SNS etc., are an integral part of this topic.

[1] V. Pecanha-Antonio, et al., Phys. Rev. B 96, 214415 (2017); [2] V. Pecanha-Antonio, et al. Phys. Rev. B 99, 134415 (2019); [3] F. Zhu, et al., Phys. Rev. Research 2, 043100 (2020); [4] F. Zhu, et al., Sci. Adv. 7, eabi7532 (2021); [5] L.C. Zhang, et al., Phys. Rev. B 103, 134414 (2021); [6] X. Mi, et al., Phys. Rev. B 103, 174413 (2021); [7] K.X. Zhang, et al., ACS Appl. Mater. Interfaces 13, 20788 (2021); [8] W. Jin, et al., Phys. Rev. B 105, L180504 (2022); [9] I. Živković, et al., Phys. Rev. Lett. 127, 157204 (2021).