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arXiv · 0710.0695

Exciton spectroscopy of hexagonal boron nitride using non-resonant x-ray Raman scattering

Yejun Feng·J. A. Soininen·A. L. Ankudinov·J. O. Cross·G. T. Seidler·A. T. Macrander·J. J. Rehr·E. L. Shirley
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Abstract

We report non-resonant x-ray Raman scattering (XRS) measurements from hexagonal boron nitride for transferred momentum from 2 to 9 $\mathrmÅ^{-1}$ along directions both in and out of the basal plane. A symmetry-based argument, together with real-space full multiple scattering calculations of the projected density of states in the spherical harmonics basis, reveals that a strong pre-edge feature is a dominantly $Y_{10}$-type Frenkel exciton with no other \textit{s}-, \textit{p}-, or \textit{d}- components. This conclusion is supported by a second, independent calculation of the \textbf{q}-dependent XRS cross-section based on the Bethe-Salpeter equation.

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Yejun Feng, J. A. Soininen, A. L. Ankudinov, J. O. Cross, G. T. Seidler, A. T. Macrander, J. J. Rehr, E. L. Shirley. 2007-10-03. Exciton spectroscopy of hexagonal boron nitride using non-resonant x-ray Raman scattering. https://doi.org/10.1103/physrevb.77.165202

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