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arXiv · 0711.4233

Static structure factor for graphene in a magnetic field

K. Shizuya
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Abstract

A close study is made of the static structure factor for graphene in a magnetic field at integer filling factors nu, with focus on revealing possible signatures of "relativistic" quantum field theory in the low-energy physics of graphene. It is pointed out, in particular, that for graphene even the vacuum state has a nonzero density spectral weight, which, together with the structure factor for all nu, grows significantly with increasing wave vector; such unusual features of density correlations are a "relativistic" effect deriving from massless Dirac quasiparticles in graphene. Remarkably it turns out that the zero-energy Landau levels of electrons or holes, characteristic to graphene, remain indistinguishable in density response from the vacuum state, although they are distinct in Hall conductance.

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K. Shizuya. 2007-11-27. Static structure factor for graphene in a magnetic field. https://doi.org/10.1103/physrevb.77.075419

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