Correlation between Propagation Length and Surface Roughness

Correlation between Propagation Length and Surface Roughness 

On an ideally flat metal surface the SEW absorption is related to the electron collisions with phonons, impurities and other electrons. Surface roughness introduces an additional decay path for the SEWs. The reason for this is twofold. 

4) The absorption coefficient is defined as a = 2 Im with q the wave vector of surface polariton. 

the mean free path of conduction electrons is reduced due to scattering on surface defects. Secondly, the SEW is scattered on surface roughness, resulting in emission of light (Section 3.3.4). This correlation can be used, for example, to control the quality of metal mirrors (Zhizhin et al. 1982). 

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