Single crystal growth and superconducting properties of the Bi(S,Se)2-based superconductor

Introduction After the discovery of superconductivity in Bi4O4S3 [1], much attention has been paid to synthesizing a new superconductors. The BiS2-based compounds have a layered structure similar to those of cuprates or Fe-based superconductors. In these compounds, superconducting layers and blocking layers are stacked alternatively. Many BiS2-based superconductors have been found by arranging the blocking layer so far. The modification in superconducting layer is important to clarify the superconducting mechanism of BiS2-based superconductor and the single crystal preparation is necessary to discuss such a intrinsic properties. In this study, we perform the single crystal growth of La(O,F)Bi(S,Se)2 and investigate the substitution effect for the superconducting properties by replacing S with Se. Results and discussion Single crystals of LaO1-xFxBiS2-ySey (0?y?2) were synthesized by CsCl flux method. The single crystals was plate-like shape with approximately 1 mm2 in size, which is enough to perform various characteristic measurements, such as single crystal X-ray analysis and electrical resistivity measurement, and so on. We will discuss the crystal structure, electrical resistivity and magnetic properties in detail. [1] Y. Mizuguchi et al.,Phys. Rev. B 86,220510(2012)