Presentation Information
[PC4-06]Effect of elemental substitution on La site in La(O, F)(Bi, Sn)S2
*Ryoya Tanabe1, Yuto Miyake1, Shogo Kuwahara1, Tadataka Watanabe1, Satoshi Demura1 (1. CST, Nihon Univ. (Japan))
Keywords:
Single crystal,Superconductivity,BiCh2-based superconductors
BiS2-based superconductor La(O, F)BiS2 has a layered crystal structure consisting of a charge supply layer formed by rare earth oxides and two conductive BiS2 layers. LaOBiS2 exhibits semiconducting properties but becomes a superconductor when some of the Oxygen (O) is replaced with Fluorine (F). The superconducting transition occurred at around 3K. A few percent substitution of Lead (Pb) or Tin (Sn) at the Bi sites La(O,F)BiS2 increased the superconducting transition temperature (Tc) to approximately twice. However, the mechanism for the enhancement of superconductivity by these elemental substitutions is not yet understood and remains under debate. In this study, we examined the effects of element substitution at the La site in La(O, F)(Bi, Sn)S2 on its superconducting properties. Single crystals of La1-xAxO0.4F0.6Bi0.88Sn0.12S2 (A: substituting element) were synthesized via the molten flux method, and their physical properties were characterized using X-ray diffraction, electrical resistivity measurements, and compositional analysis. As a result of the synthesis, single crystals were successfully obtained. The lattice constant along the c-axis is varied by the substitution, indicating that the element substitution has succeeded. In the presentation, we will discuss the effects of element substitution based on more detailed evaluations of the physical properties.