Electronic structure and coexistence of superconductivity with magnetism in RbEuFe4As4

DOI: 10.1103/PhysRevB.103.174517

Authors: T. K. Kim (Diamond Light Source) , K. S. Pervakov (Lebedev Physical Institute) , D. V. Evtushinsky (École Polytechnique Fédérale de Lausanne) , S. W. Jung (Diamond Light Source; Gyeongsang National University) , G. Poelchen (Technische Universität Dresden; European Synchrotron Radiation Facility) , K. Kummer (European Synchrotron Radiation Facility) , V. A. Vlasenko (Lebedev Physical Institute) , A. V. Sadakov (Lebedev Physical Institute) , A. S. Usoltsev (0000-0003-1691-8038) , V. M. Pudalov (Lebedev Physical Institute) , D. Roditchev (LPEM, ESPCI Paris, PSL Research University, CNRS; Sorbonne Universite; Moscow Institute of Physics and Technology) , V. S. Stolyarov (Moscow Institute of Physics and Technology; N. L. Dukhov All-Russia Research Institute of Automatics) , D. V. Vyalikh (Donostia International Physics Center (DIPC); IKERBASQUE, Basque Foundation for Science) , V. Borisov (Goethe-Universität Frankfurt) , R. Valentí (Goethe-Universität Frankfurt) , A. Ernst (Johannes Kepler Universität; Max-Planck-Institut für Mikrostrukturphysik) , S. V. Eremeev (Institute of Strength Physics and Materials Science, Russian Academy of Sciences; Saint Petersburg State University) , E. V. Chulkov (Donostia International Physics Center (DIPC); Saint Petersburg State University; Universidad del País Vasco UPV/EHU)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Physical Review B , VOL 103

State: Published (Approved)
Published: May 2021
Diamond Proposal Number(s): 19041 , 22192

Abstract: In the novel stoichiometric iron-based material RbEuFe 4 As 4 , superconductivity coexists with a peculiar long-range magnetic order of Eu 4f states. Using angle-resolved photoemission spectroscopy, we reveal a complex three-dimensional electronic structure and compare it with density functional theory calculations. Multiple superconducting gaps were measured on various sheets of the Fermi surface. High-resolution resonant photoemission spectroscopy reveals magnetic order of the Eu 4f states deep into the superconducting phase. Both the absolute values and the anisotropy of the superconducting gaps are remarkably similar to the sibling compound without Eu, indicating that Eu magnetism does not affect the pairing of electrons. A complete decoupling between Fe- and Eu-derived states was established from their evolution with temperature, thus unambiguously demonstrating that superconducting and a long-range magnetic orders exist independently from each other. The established electronic structure of RbEuFe 4 As 4 opens opportunities for the future studies of the highly unorthodox electron pairing and phase competition in this family of iron-based superconductors with doping.

Journal Keywords: Electronic structure; Magnetic order; Magnetic phase transitions; Multiband superconductivity; Superconducting gap; Superconducting phase transition; Iron-based superconductors; Angle-resolved photoemission spectroscopy; DFT+U

Subject Areas: Physics, Materials


Instruments: I05-ARPES

Other Facilities: BOREAS beamline at ALBA

Added On: 26/05/2021 07:06

Documents:
PhysRevB.103.174517.pdf

Discipline Tags:

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

Technical Tags:

Spectroscopy Angle Resolved Photoemission Spectroscopy (ARPES)