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arXiv · 0903.2369

Possible Fractional Quantum Hall Effect in Graphite

Y. Kopelevich·B. Raquet·M. Goiran·W. Escoffier·R. R. da Silva·J. C. Medina Pantoja·I. A. Lukyanchuk·A. Sinchenko·P. Monceau
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Abstract

Measurements of basal plane longitudinal rho_b(B) and Hall rho_H(B) resistivities were performed on highly oriented pyrolytic graphite (HOPG) samples in pulsed magnetic field up to B = 50 T applied perpendicular to graphene planes, and temperatures 1.5 K < T < 4.2 K. At B > 30 T and for all studied samples, we observed a sign change in rho_H(B) from electron- to hole-like. For our best quality sample, the measurements revealed the enhancement in rho_b(B) for B > 34 T (T = 1.8 K), presumably associated with the field-driven charge density wave or Wigner crystallization transition. Besides, well defined plateaus in rho_H(B) were detected in the ultra-quantum limit revealing the signatures of fractional quantum Hall effect in graphite.

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Y. Kopelevich, B. Raquet, M. Goiran, W. Escoffier, R. R. da Silva, J. C. Medina Pantoja, I. A. Lukyanchuk, A. Sinchenko, P. Monceau. 2009-03-13. Possible Fractional Quantum Hall Effect in Graphite. https://doi.org/10.1103/physrevlett.103.116802

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