M. Tsujimoto, H. Kambara, Y. Maeda, Y. Yoshioka, Y. Nakagawa, and I. Kakeya “Dynamic Control of Temperature Distributions in Stacks of Intrinsic Josephson Junctions in Bi2Sr2CaCu2O8+δ for Intense Terahertz Radiation”
S. Komori, R. Inaba, K. Kaneko, S. Fujita, I. Kakeya, and M. Suzuki
ABSTRACT
Thin films of single-crystal Pb1−yBiySr2Y1−xCaxCu2O7+δ (PbBi1212) were grown on SrTiO3 (100) substrates by a two-step growth technique in which an amorphous film is annealed at 970 ∘C in a closed ceramic container prepared using the same material as the film. We find that PbBi1212 exhibits superconductivity when the Ca concentration xexceeds 0.3. The effective number of holes per Cu atom neff is well described as neff=0.34x. The highest onset temperature for the superconducting transition attained in the present study is 65 K. The resistivity measurement in a magnetic field reveals that the coherence lengths of Pb1212 (y=0) are approximately 25 and 2.7 Å along the abplane and the c axis, respectively.
DOI: http://dx.doi.org/10.1103/PhysRevB.89.174509
京都大学の超伝導・真空電子デバイスに関する研究室, Research group for superconducting and vaccum electronics in Kyoto Univ.