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Optical Resonances in Reflectivity near Crystal Modes with Spatial Dispersion

I. Kaelin·Ch. Helm·G. Blatter
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Abstract

We study the effect of spatial dispersion of crystal modes on optical properties such as the reflectivity $R$. As an example for isotropic media, we investigate the simplest model for phonons in ionic crystals and compare with previous results for highly anisotropic plasmons, which are now understood from a more general point of view. As a consequence of the wave vector dependence of the dielectric function small changes in the lineshape are predicted. Beyond that, if the frequency of minimal $R$ is near a pole of the dispersionless dielectric function, the relative amplitude of dips in $R$ with normal and anomalous dispersion differ significantly, if dissipation and disorder are low.

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I. Kaelin, Ch. Helm, G. Blatter. 2003-05-14. Optical Resonances in Reflectivity near Crystal Modes with Spatial Dispersion. https://doi.org/10.1103/physrevb.68.012302

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