Abstract.
Based on numerical studies, we show that localisation is a common phenomenon in resonators exhibiting some kind of geometrical complexity. In two-dimensional (2d) shallow cavities of irregular shape, localisation effects are due to spatial decoherence in a major fraction of the volume. In 2d shallow cavities of regular geometry with embedded absorbing material of irregular shape, one observes the appearance of eigenmodes localised in both, the absorbing and the non-absorbing media. Those modes are thought to be responsible for increased dissipation. These results may be a hint to understand why natural or practical systems absorbing wave energy are found, or built, with complex geometry.
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Sapoval, B., Félix, S. & Filoche, M. Localisation and damping in resonators with complex geometry. Eur. Phys. J. Spec. Top. 161, 225–232 (2008). https://doi.org/10.1140/epjst/e2008-00763-2
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DOI: https://doi.org/10.1140/epjst/e2008-00763-2