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arXiv · 1106.5222

Four Dimensional Graphene

Abstract

Mimicking pristine 2D graphene, we revisit the BBTW model for 4D lattice QCD given in ref.[5] by using the hidden SU(5) symmetry of the 4D hyperdiamond lattice H_4. We first study the link between the H_4 and SU(5); then we refine the BBTW 4D lattice action by using the weight vectors λ_1, λ_2, λ_3, λ_4, λ_5 of the 5-dimensional representation of SU(5) satisfying Σ_iλ_i=0. After that we study explicitly the solutions of the zeros of the Dirac operator D in terms of the SU(5) simple roots α_1, α_2, α_3, α_4 generating H_4; and its fundamental weights ω_1, ω_2, ω_3, ω_4 which generate the reciprocal lattice H_4^\ast. It is shown, amongst others, that these zeros live at the sites of H_4^\ast; and the continuous limit D is given by ((id\surd5)/2) γ^\muk_μwith d, γ^μand k_μstanding respectively for the lattice parameter of H_4, the usual 4 Dirac matrices and the 4D wave vector. Other features such as differences with BBTW model as well as the link between the Dirac operator following from our construction and the one suggested by Creutz using quaternions, are also given. Keywords: Graphene, Lattice QCD, 4D hyperdiamond, BBTW model, SU(5) Symmetry.

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L. B Drissi, E. H Saidi, M. Bousmina. 2011-06-26. Four Dimensional Graphene. https://doi.org/10.1103/physrevd.84.014504

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