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arXiv · 0907.1111

Supermetallic conductivity in bromine-intercalated graphite

S. Tongay·J. Hwang·D. B. Tanner·H. K. Pal·D. Maslov·A. F. Hebard
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Abstract

Exposure of highly oriented pyrolytic graphite to bromine vapor gives rise to in-plane charge conductivities which increase monotonically with intercalation time toward values (for ~6 at% Br) that are significantly higher than Cu at temperatures down to 5 K. Magnetotransport, optical reflectivity and magnetic susceptibility measurements confirm that the Br dopes the graphene sheets with holes while simultaneously increasing the interplanar separation. The increase of mobility (~ 5E4 cm^2/Vs at T=300 K) and resistance anisotropy together with the reduced diamagnetic susceptibility of the intercalated samples suggests that the observed supermetallic conductivity derives from a parallel combination of weakly-coupled hole-doped graphene sheets.

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S. Tongay, J. Hwang, D. B. Tanner, H. K. Pal, D. Maslov, A. F. Hebard. 2009-07-06. Supermetallic conductivity in bromine-intercalated graphite. https://doi.org/10.1103/physrevb.81.115428

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