Collective modes of the massless Dirac plasma

S. Das Sarma; E. H. Hwang

doi:10.1103/physrevlett.102.206412

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arXiv · 0902.3822

Collective modes of the massless Dirac plasma

S. Das Sarma·E. H. Hwang

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Abstract

We develop a theory for the long-wavelength plasma oscillation of a collection of charged massless Dirac particles in a solid, as occurring for example in doped graphene layers, interacting via the long-range Coulomb interaction. We find that the long-wavelength plasmon frequency in such a doped massless Dirac plasma is explicitly non-classical in all dimensions with the plasma frequency being proportional to \hbar^{-1/2}. We also show that the long wavelength plasma frequency of the D-dimensional superlattice made from such a plasma does not agree with the corresponding (D + 1)-dimensional bulk plasmon frequency. We compare and contrast such Dirac plasmons with the well-studied regular palsmons in metals and doped semiconductors which manifest the usual classical long wavelength plasma oscillation.

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BibTeX RIS

S. Das Sarma, E. H. Hwang. 2009-02-23. Collective modes of the massless Dirac plasma. https://doi.org/10.1103/physrevlett.102.206412

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