Decoupling of lattice and orbital degrees of freedom in an iron-pnictide superconductor

DOI: 10.1103/PhysRevResearch.3.023220

Authors: C. E. Matt (Swiss Light Source; Universität Zürich) , O. Ivashko (Universität Zürich) , M. Horio (Universität Zürich) , J. Choi (Universität Zürich) , Q. Wang (Universität Zürich) , D. Sutter (University of Zurich) , N. Dennler (Universität Zürich) , M. H. Fischer (Universität Zürich) , S. Katrych (École Polytechnique Fédérale de Lausanne (EPFL)) , L. Forro (École Polytechnique Fédérale de Lausanne (EPFL)) , J. Ma (Swiss Light Source) , B. Fu (Swiss Light Source) , B. Q. Lv (Swiss Light Source) , M. V. Zimmermann (Deutsches Elektronen-Synchrotron DESY) , T. K. Kim (Diamond Light Source) , N. C. Plumb (Swiss Light Source) , N. Xu (Swiss Light Source) , M. Shi (Swiss Light Source) , Johan Chang (Universität Zürich)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Physical Review Research , VOL 3

State: Published (Approved)
Published: June 2021
Diamond Proposal Number(s): 16104

Abstract: The interplay between structural and electronic phases in iron-based superconductors is a central theme in the search for the superconducting pairing mechanism. While electronic nematicity is competing with superconductivity, the effect of purely structural orthorhombic order is unexplored. Here, using x-ray diffraction and angle-resolved photoemission spectroscopy, we reveal a structural orthorhombic phase in the electron-doped iron-pnictide superconductor Pr 4 Fe 2 As 2 Te 0.88 O 4 ( T c = 25 K), which is distinct from orthorhombicity in the nematic phase in underdoped pnictides. Despite the high electron doping we find an exceptionally high orthorhombic onset temperature ( T ort ∼ 250 K), no signatures of phase competition with superconductivity, and absence of electronic nematic order as the driving mechanism for orthorhombicity. Combined, our results establish a high-temperature phase in the phase diagram of iron-pnictide superconductors and impose strong constraints for the modeling of their superconducting pairing mechanism.

Journal Keywords: Crystal structure; Phase transitions; Structural order parameter; Superconductivity; Transition temperature; Iron-based superconductors; Strongly correlated systems; Angle-resolved photoemission spectroscopy; Density functional theory; X-ray diffraction

Subject Areas: Physics, Materials


Instruments: I05-ARPES

Other Facilities: P07 at PETRA III; SIS at Swiss Light Source

Added On: 28/06/2021 11:57

Documents:
PhysRevResearch.3.023220.pdf

Discipline Tags:

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

Technical Tags:

Spectroscopy Angle Resolved Photoemission Spectroscopy (ARPES)