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arXiv · 1105.4679

Theoretical study of X-ray absorption of three-dimensional topological insulator $\mathrm{Bi}_2\mathrm{Se}_3$

Hyun C. Lee
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Abstract

X-ray absorption edge singularity which is usually relevant for metals is studied for the prototype topological insulator $\mathrm{Bi}_2\mathrm{Se}_3$. The generalized integral equation of Nozières and Dominicis type for X-ray edge singularity is derived and solved. The spin texture of surfaces states causes a component of singularity dependent on the helicity of the spin texture. It also yields another component for which the singularity from excitonic processes is absent.

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Hyun C. Lee. 2011-05-24. Theoretical study of X-ray absorption of three-dimensional topological insulator $\mathrm{Bi}_2\mathrm{Se}_3$. https://doi.org/10.1103/physrevb.83.193107

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