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arXiv · 1710.02657

Spin-density wave state in simple hexagonal graphite

K. S. Mosoyan·A. V. Rozhkov·A. O. Sboychakov·A. L. Rakhmanov
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Abstract

Simple hexagonal graphite, also known as AA graphite, is a metastable configuration of graphite. Using tight-binding approximation it is easy to demonstrate that AA graphite is a metal with well-defined Fermi surface. The Fermi surface consists of two sheets, each shaped like a rugby ball. One sheet corresponds to electron states, another corresponds to hole states. The Fermi surface demonstrates good nesting: a suitable translation in the reciprocal space superposes one sheet onto another. In the presence of the electron-electron repulsion a nested Fermi surface is unstable with respect to spin-density wave ordering. This instability is studied using the mean-field theory at zero temperature, and the spin-density wave order parameter is evaluated.

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K. S. Mosoyan, A. V. Rozhkov, A. O. Sboychakov, A. L. Rakhmanov. 2018-02-16. Spin-density wave state in simple hexagonal graphite. https://doi.org/10.1103/physrevb.97.075131

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