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Dirac Fermions in Graphite

posted Dec 29, 2009, 12:15 AM by Igor Lukyanchuk   [ updated Dec 5, 2010, 12:58 PM by Igor Lukyanchuk ]
How realistic may be relativistic field models to describe  phenomena occurring in a condensed matter system ?  Such question should be particularly relevant for the systems  with massless Dirac fermions. The first unambiguous experim ental evidence for Dirac fermions occurrence in solids has  been reported by I.Lukyanchuk and Y.Kopelevich for graphite in 2004, one year before discovery of Dirac Fermions in graphite mono-layer (Graphene).  The identification of Dirac fermions became possible due to  phase-frequency analysis of quantum de Haas van Alphen and Shubnikov de Haas oscillations.  Actually, this method allows the efficient phase definition in any quantum oscillation phenomena and can be considered as a new tool in the condensed matter research. The identification of two-dimensional Dirac fermions in graphite undoubtedly makes this system a natural solid state laboratory to test predictions of relativistic theories of (2+1)-dimensional Dirac fermions.

Read more:
Phase analysis of quantum oscillations in graphite,
I. Luk'yanchuk, Y. Kopelevich, Phys. Rev. Lett., 93, 166402 (2004)
Dirac and normal fermions in graphite and graphene: Implications of the quantum Hall effect
I. A. Lukyanchuk and Y. Kopelevich, Phys. Rev. Lett., 97, 256801 (2006)
Lattice-induced double-valley degeneracy lifting in graphene by a magnetic field,
I. Luk'yanchuk and A. Bratkovsky; Phys. Rev. Lett., 100, 176404, (2008)
Searching for the Fractional Quantum Hall Effect in Graphite
Y. Kopelevich, B. Raquet, M. Goiran,... I. A. Lukyanchuk,.; et al., Phys. Rev. Lett., 103, 116802 (2009)