Abstract
Polycrystalline or single crystal HgI2 intercalated Bi2Sr2CaCu2Oy, (Bi2212) superconductors have been synthesized and their structure and superconductivity have been studied. According to X-ray diffraction, the a and c axis-lengths were estimated to be 0.54 nm and 2.26 um, respectively. The expansion of c axis length was 0.72 nm, compared to that of host Bi2212 (3.09nm/2=1.54nm), while a axis length did not changed. From ac susceptibility and resistivity measurements, superconducting transition onset temperature (Tc) for polycrystalline HgI2 intercalate was found to be 82K, which is higher than that of host 75K. On the other hand, resistivity measurements for single crystal HgI2 intercalate was showed to be 75K, which is lower than that of host 95K. The effect of HgI2 intercalation on the superconductivity is discussed from the viewpoint of hole concentration change.
