In-plane Charge Fluctuations in Bismuth Sulfide Superconductors

Abstract

Evidence for local charge fluctuations linked to a charge disproportionation of the Bi ions in the distorted lattice of superconducting LaO${}_{1-x}$F${}_x$ BiS${}_2$ is presented. In-plane short-range distortions of sulfur atoms up to 0.3 Å in magnitude break site symmetry and create two distinct environments around Bi. Out-of-plane motion of apical sulfur brings it closer to the La-O/F doping layer with increasing $x$ that may lead to a charge transfer conduit between the doping layers and the superconducting BiS${}_2$ planes. The mechanism for superconductivity may arise from the interplay between charge density fluctuations and an enhanced spin-orbit coupling suggested theoretically, that induces spin polarization.

References in corpus (6)

• Superconductivity Appears in the Vicinity of an Insulating-Like Behavior in CeO${}_{1-x}$F${}_x$BiS${}_2$
• Minimal electronic models for superconducting BiS${}_2$ layers
• Superconductivity of F-substituted LnOBiS2 (Ln = La, Ce, Pr, Nd, Yb) compounds
• Ferroelectric Soft Phonons, Charge Density Wave Instability and Strong Electron-Phonon Coupling in BiS2-Layered Superconductors
• Pressure Study of BiS2-Based Superconductors Bi4O4S3 and La(O,F)BiS2
• Evolution of superconductivity in LaO1-xFxBiS2 prepared by high pressure technique

Cited by in corpus (11)

• Search and design of nonmagnetic centrosymmetric layered crystals with large local spin polarization
• Classification of multipole superconductivity in multi-orbital systems and its implications
• SnAs-based layered superconductor NaSn2As2
• Evolution of Anisotropic Displacement Parameters and Superconductivity with Chemical Pressure in BiS2-Based REO0.5F0.5BiS2 (RE = La, Ce, Pr, and Nd)
• Bulk Superconductivity Induced by In-plane Chemical Pressure Effect in Eu0.5La0.5FBiS2-xSex
• Predicted electronic markers for polytypes of LaOBiS2 examined via angular resolved photoemission spectroscopy
• Bulk Superconductivity Induced by Se Substitution in BiCh2-Based Layered Compounds Eu0.5Ce0.5FBiS2-xSex
• Charge Fluctuations in the NdO${}_{1-x}$F${}_x$BiS${}_2$ Superconductors
• Enhanced thermoelectricity by controlled local structure in bismuth-chalcogenides
• Lattice Anharmonicity in BiS2-Based Layered Superconductor RE(O,F)BiS2 (RE = La, Ce, Pr, Nd)
• Crystal Structure and Thermoelectric Transport Properties of As-Doped Layered Pnictogen Oxyselenides NdO0.8F0.2Sb1-xAsxSe2