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Anderson Localization - phonons, bosons, light

Direct observation of Anderson localization of matter-waves in a controlled disorder

Juliette Billy, Vincent Josse, Zhanchun Zuo, Alain Bernard1, Ben Hambrecht1, Pierre Lugan1, David Clément, Laurent Sanchez-Palencia, Philippe Bouyer1 & Alain Aspect

not a sharp mobility edge, but diffusion crossover?! - Diffusons, Locons, Propagons: Character of Atomic Vibrations in Amorphous Si Philip B. Allen

Since $95\%$ of the states in amorphous Si, and probably many other glasses as well, are diffusons, we should
understand their properties
Our most important conclusion is that the “reincrease” of thermal conductivity above the plateau region is attributable to heat carried by “diffuson” modes in much the way imagined by Birch, Clark, and Kittel, and that the plateau is a simple crossover region, not requiring any new physics to explain.