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Magnetic-field induced superconductor-metal-insulator transitions in bismuth metal-graphite

Masatsugu Suzuki·Itsuko S. Suzuki·Robert Lee·Jürgen Walter
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Abstract

Bismuth-metal graphite (MG) has a unique layered structure where Bi nanoparticles are encapsulated between adjacent sheets of nanographites. The superconductivity below $T_{c}$ (= 2.48 K) is due to Bi nanoparticles. The Curie-like susceptibility below 30 K is due to conduction electrons localized near zigzag edges of nanographites. A magnetic-field induced transition from metallic to semiconductor-like phase is observed in the in-plane resistivity $ρ_{a}$ around $H_{c}$ ($\approx$ 25 kOe) for both $H$$\perp$$c$ and $H$$\parallel$$c$ ($c$: c axis). A negative magnetoresistance in $ρ_{a}$ for $H$$\perp$$c$ (0$ $ 40 kOe) suggest the occurrence of two-dimensional weak localization effect.

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Masatsugu Suzuki, Itsuko S. Suzuki, Robert Lee, Jürgen Walter. 2003-08-15. Magnetic-field induced superconductor-metal-insulator transitions in bismuth metal-graphite. https://doi.org/10.1103/physrevb.66.014533

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