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arXiv · cond-mat/9912194

High-Field Quasiparticle Tunneling in Bi_2Sr_2CaCu_2O_8+delta: Negative Magnetoresistance in the Superconducting State

N. Morozov·L. Krusin-Elbaum·T. Shibauchi·L. N. Bulaevskii·M. P. Maley·Yu. I. Latyshev·T. Yamashita
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Abstract

We report on the c-axis resistivity rho_c(H) in Bi_2Sr_2CaCu_2O_{8+δ} that peaks in quasi-static magnetic fields up to 60 T. By suppressing the Josephson part of the two-channel (Cooper pair/quasiparticle) conductivity σ_c (H), we find that the negative slope of ρ_c(H) above the peak is due to quasiparticle tunneling conductivity σ_q(H) across the CuO_2 layers below H_{c2}. At high fields (a) σ_q(H) grows linearly with H, and (b) ρ_c(T) tends to saturate (sigma_c \neq 0) as T->0, consistent with the scattering at the nodes of the d-gap. A superlinear sigma_q(H) marks the normal state above T_c.

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N. Morozov, L. Krusin-Elbaum, T. Shibauchi, L. N. Bulaevskii, M. P. Maley, Yu. I. Latyshev, T. Yamashita. 1999-12-10. High-Field Quasiparticle Tunneling in Bi_2Sr_2CaCu_2O_8+delta: Negative Magnetoresistance in the Superconducting State. https://doi.org/10.1103/physrevlett.84.1784

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