2004/05/06 by K. Kudo, Kudo, K., Y. Miyoshi +6
Materials Science · Physics and Astronomy · #Magnetic Properties and Applications #Magnetic properties of thin films #Physics of Superconductivity and Magnetism #cond-mat.supr-con
paper · pdf · doi:10.48550/arxiv.cond-mat/0405106
12 pages, 4 figures, 1 table
arxiv created 2004/09/24 · arxiv updated 2009/12/01
We report the out-of-plane resistivity in the systematically oxygen-controlled single crystals Bi1.74Pb0.38Sr1.88CuO6+δ in magnetic fields parallel to the c-axis. Two characteristic temperatures T^* and T** are found at which a semiconductor-like upturn starts to develop and the magnetoresistance changes its sign from positive to negative at lower temperature, respectively. The obtained phase diagram strongly suggests that the pseudogap temperature correlating to the superconducting gap is not T* but T**. The gap opened at T^* may relate to another phenomenon with the different energy scale such as the antiferromagnetic excitation due to the exchange interaction between Cu2+ spins.