Origin of Lattice Spin in Graphitic Systems

Kumar Abhinav; Prasanta K. Panigrahi

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arXiv · 1512.06037

Origin of Lattice Spin in Graphitic Systems

Kumar Abhinav·Prasanta K. Panigrahi

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Abstract

Lattice spin, in planar condensed matter system with emergent Dirac dispersion, is shown to emerge from the inherent SU(2) symmetry, arising through Schwingers angular momentum construction from anti-commuting Heisenberg operators of the sub-lattices. The presence of a mass term in the emergent Dirac dispersion is essential for the existence of this spin. The usual hopping term, that entangles the two sub-lattices, leads to the orbital counterpart. Relative sub-lattice displacements, that couple to the effective Dirac fermions like U(1) gauge fields, do not effect the lattice spin.

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Kumar Abhinav, Prasanta K. Panigrahi. 2015-12-18. Origin of Lattice Spin in Graphitic Systems. https://arxiv.org/abs/1512.06037

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