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arXiv · 0708.1366

X-ray edge problem of graphene

S. -R. Eric Yang·Hyun C. Lee
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Abstract

The X-ray edge problem of graphene with the Dirac fermion spectrum is studied. At half-filling the linear density of states suppresses the singular response of the Fermi liquid, while away from half-filling the singular features of the Fermi liquid reappear. The crossover behavior as a function of the Fermi energy is examined in detail. The exponent of the power-law absorption rate depends both on the intra- and inter-valley scattering, and it changes as a function of the Fermi energy, which may be tested experimentally.

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S. -R. Eric Yang, Hyun C. Lee. 2007-11-14. X-ray edge problem of graphene. https://doi.org/10.1103/physrevb.76.245411

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