Probing the reconstructed Fermi surface of antiferromagnetic BaFe2As2 in one domain

DOI: 10.1038/s41535-019-0174-z

Authors: Matthew D. Watson (Diamond Light Source) , Pavel Dudin (Diamond Light Source) , Luke C. Rhodes (Diamond Light Source; University of St. Andrews; Royal Holloway, University of London) , Daniil V. Evtushynsky (Ecole Polytechnique Federale de Lausanne) , Hideaki Iwasawa (Diamond Light Source; Hiroshima University) , Saicharan Aswartham (Leibniz Institute for Solid State and Materials Research) , Sabine Wurmehl (Leibniz Institute for Solid State and Materials Research) , Bernd Büchner (Leibniz Institute for Solid State and Materials Research; Technische Universität Dresden) , Moritz Hoesch (Diamond Light Source; Deutsches Elektronen-Synchrotron) , Timur K. Kim (Diamond Light Source)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Npj Quantum Materials , VOL 4

State: Published (Approved)
Published: July 2019
Diamond Proposal Number(s): 15074 , 19041

Abstract: A fundamental part of the puzzle of unconventional superconductivity in the Fe-based superconductors is the understanding of the magnetic and nematic instabilities of the parent compounds. The issues of which of these can be considered the leading instability, and whether weak- or strong-coupling approaches are applicable, are both critical and contentious. Here, we revisit the electronic structure of BaFe2As2 using angle-resolved photoemission spectroscopy (ARPES). Our high-resolution measurements of samples “detwinned” by the application of a mechanical strain reveal a highly anisotropic 3D Fermi surface in the low-temperature antiferromagnetic phase. By comparison of the observed dispersions with ab initio calculations, we argue that overall it is magnetism, rather than orbital/nematic ordering, which is the dominant effect, reconstructing the electronic structure across the Fe 3d bandwidth. Finally, using a state-of-the-art nano-ARPES system, we reveal how the observed electronic dispersions vary in real space as the beam spot crosses domain boundaries in an unstrained sample, enabling the measurement of ARPES data from within single antiferromagnetic domains, and showing consistence with the effective mono-domain samples obtained by detwinning.

Journal Keywords: Electronic properties and materials; Superconducting properties and materials

Diamond Keywords: Antiferromagnetism

Subject Areas: Physics, Materials


Instruments: I05-ARPES

Added On: 19/07/2019 00:40

Documents:
s41535-019-0174-z.pdf

Discipline Tags:

Superconductors Quantum Materials Hard condensed matter - electronic properties Physics Magnetism Materials Science

Technical Tags:

Spectroscopy Angle Resolved Photoemission Spectroscopy (ARPES)