3:00 PM - 3:15 PM
[16p-D209-6] Superconductivity in Pr2Ba4Cu7O15-δ IV: Cu Nuclear-Spin Evidence of Chain-Driven Superconductivity
Keywords:superconductor, cuprate, double chains
Pr2Ba4Cu7O17-δ (Pr247) has a hybrid structure composed of Pr123 and Pr124. If well-prepared, Pr247 was suggested to be superconducting, but the volume fraction was less than 10%. Recently, we have succeeded in synthesizing Pr247 of 100% superconducting fraction. In addition, through our Cu-NQR frequency spectra, we clarified that the CuO2 planes are in an insulating and antiferromagnetic state. Here we report from Cu-NQR spin-lattice relaxation rate that superconducting gap clearly opens up in the Cu2O2 double chains. This indicates that, unlike all the other cuprates, the superconductivity is driven not by the planes but by the double chains.