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.
@article{arxiv.0903.2369,
title = {Possible Fractional Quantum Hall Effect in Graphite},
author = {Y. Kopelevich and B. Raquet and M. Goiran and W. Escoffier and R. R. da Silva and J. C. Medina Pantoja and I. A. Lukyanchuk and A. Sinchenko and P. Monceau},
journal= {arXiv preprint arXiv:0903.2369},
year = {2015}
}