Pseudogap Phase Boundary in Overdoped Bi_2Sr_2CaCu_2O_8 Studied by Measuring Out-of-plane Resistivity under the Magnetic Fields

Kousuke Murata; Haruki Kushibiki; Takao Watanabe; Kazutaka Kudo; Terukazu Nishizaki; Norio Kobayashi; Kazuyoshi Yamada; Takashi Noji; Yoji Koike

doi:10.1016/j.physc.2010.01.027

arXiv · 1002.3014

Pseudogap Phase Boundary in Overdoped Bi_2Sr_2CaCu_2O_8 Studied by Measuring Out-of-plane Resistivity under the Magnetic Fields

Kousuke Murata·Haruki Kushibiki·Takao Watanabe·Kazutaka Kudo·Terukazu Nishizaki·Norio Kobayashi·Kazuyoshi Yamada·Takashi Noji·Yoji Koike

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Abstract

The characteristic pseudogap temperature T* in Bi2Sr2CaCu2O8 system has been systematically evaluated as a function of doping, especially focusing on its overdoped region, by measuring the out-of-plane resistivity under the magnetic fields. Overdoped samples have been prepared by annealing TSFZ-grown Bi2Sr2CaCu2O8 single crystals under the high oxygen pressures (990 kgf/cm2). At a zero field, the out-of-plane resistivity showed a metallic behavior down to Tc (= 62 K), while under the magnetic fields of over 3 T,it showed typical upturn behavior from around 65 K upon decreasing temperature. This result suggests that the pseudogap and superconductivity are different phenomena.

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Kousuke Murata, Haruki Kushibiki, Takao Watanabe, Kazutaka Kudo, Terukazu Nishizaki, Norio Kobayashi, Kazuyoshi Yamada, Takashi Noji, Yoji Koike. 2010-02-16. Pseudogap Phase Boundary in Overdoped Bi_2Sr_2CaCu_2O_8 Studied by Measuring Out-of-plane Resistivity under the Magnetic Fields. https://doi.org/10.1016/j.physc.2010.01.027

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