Inhomogeneous charge distribution in a self-doped EuFBiS2 superconductor

T. Sugimoto, E. Paris, K. Terashima, A. Barinov, A. Giampietri, Takanori Wakita, Takayoshi Yokoya, J. Kajitani, R. Higashinaka, T. D. Matsuda, Y. Aoki, T. Mizokawa, N. L. Saini

Research output: Contribution to journalArticle

Abstract

Stoichiometric EuFBiS 2 with mixed valent Eu shows self-doped superconductivity at low temperatures due to the Eu-to-Bi charge transfer. The metallic/nonmetallic bistability of the BiS 2 layer can couple with the valence fluctuation of Eu and provide a highly susceptible electronic state. Here, we report space-resolved photoemission measurements on EuFBiS 2 revealing an inhomogeneous charge distribution with the coexistence of metallic and nonmetallic phases at mesoscopic length scales. Angle-resolved photoemission measurements using a submicron beam size have confirmed a clear Fermi surface around the zone boundaries in the metallic region, typically observed in a doped system, while it can be hardly seen in the nonmetallic region. Density functional theory calculations suggest that the out-of-plane S atom position in the structure is one of the important factors for the self-doping in this material.

Original languageEnglish
Article number064520
JournalPhysical Review B
Volume100
Issue number6
DOIs
Publication statusPublished - Aug 22 2019

    Fingerprint

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Cite this

Sugimoto, T., Paris, E., Terashima, K., Barinov, A., Giampietri, A., Wakita, T., Yokoya, T., Kajitani, J., Higashinaka, R., Matsuda, T. D., Aoki, Y., Mizokawa, T., & Saini, N. L. (2019). Inhomogeneous charge distribution in a self-doped EuFBiS2 superconductor. Physical Review B, 100(6), [064520]. https://doi.org/10.1103/PhysRevB.100.064520