Spectral Evidence for Emergent Order in Ba_{1-x}Na_{x}Fe_{2}As_{2}

M Yi; A Frano; D H Lu; Y He; Meng Wang; B A Frandsen; A F Kemper; R Yu; Q Si; L Wang; M He; F Hardy; P Schweiss; P Adelmann; T Wolf; M Hashimoto; S-K Mo; Z Hussain; M Le Tacon; A E Böhmer; D-H Lee; Z-X Shen; C Meingast; R J Birgeneau

doi:10.1103/PhysRevLett.121.127001

Spectral Evidence for Emergent Order in Ba_{1-x}Na_{x}Fe_{2}As_{2}

Phys Rev Lett. 2018 Sep 21;121(12):127001. doi: 10.1103/PhysRevLett.121.127001.

Authors

M Yi^{1

2}, A Frano^{1

3}, D H Lu⁴, Y He^{5

6}, Meng Wang⁷, B A Frandsen⁸, A F Kemper⁹, R Yu¹⁰, Q Si², L Wang^{11

12}, M He¹¹, F Hardy¹¹, P Schweiss¹¹, P Adelmann¹¹, T Wolf¹¹, M Hashimoto⁴, S-K Mo³, Z Hussain³, M Le Tacon¹¹, A E Böhmer¹¹, D-H Lee^{1

8}, Z-X Shen^{5

6}, C Meingast¹¹, R J Birgeneau^{1

8

13}

Affiliations

¹ Department of Physics, University of California Berkeley, Berkeley, California 94720, USA.
² Department of Physics and Astronomy, Rice University, Houston, Texas 77005, USA.
³ Advanced Light Source, Lawrence Berkeley National Lab, Berkeley, California 94720, USA.
⁴ Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA.
⁵ Stanford Institute of Materials and Energy Sciences, Stanford University, Stanford, California 94305, USA.
⁶ Departments of Physics and Applied Physics, and Geballe Laboratory for Advanced Materials, Stanford University, Stanford, California 94305, USA.
⁷ School of Physics, Sun Yat-Sen University, Guangzhou 510275, China.
⁸ Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
⁹ Department of Physics, North Carolina State University, Raleigh, North Carolina 27695, USA.
¹⁰ Department of Physics, Renmin University of China, Beijing 100872, China.
¹¹ Institute for Solid State Physics, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany.
¹² Kirchhoff-Institute for Physics, Universitt Heidelberg, D-69120 Heidelberg, Germany.
¹³ Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA.

PMID: 30296157
DOI: 10.1103/PhysRevLett.121.127001

Abstract

We report an angle-resolved photoemission spectroscopy study of the iron-based superconductor family, Ba_{1-x}Na_{x}Fe_{2}As_{2}. This system harbors the recently discovered double-Q magnetic order appearing in a reentrant C_{4} phase deep within the underdoped regime of the phase diagram that is otherwise dominated by the coupled nematic phase and collinear antiferromagnetic order. From a detailed temperature-dependence study, we identify the electronic response to the nematic phase in an orbital-dependent band shift that strictly follows the rotational symmetry of the lattice and disappears when the system restores C_{4} symmetry in the low temperature phase. In addition, we report the observation of a distinct electronic reconstruction that cannot be explained by the known electronic orders in the system.