High-Pressure Synthesis of SmFeAsO1-xFx (x=0.2) Single Crystals

Abstract

Fluorine-doped SmFeAsO1-xFx single crystals with the nominal value of x=0.2 were grown at 1350-1450 ℃ under the pressure of 3.3 GPa by using the self-flux method. Plate-shaped single crystals in the range of a few-150 ㎛ in their lateral size were obtained. The detailed crystal structure was analyzed by using the x-ray diffractometry. Superconducting transition temperature, determined by the resistive transition, of a single crystal was about 49 K with a narrow resistive transition width of ~1 K. A relatively sharp transition, a low residual resistivity, and a large residual resistivity ratio compared with those reported for REFeAsO1-xFx (RE=Sm, Nd) single crystals indicate the high quality of our single crystals.