The solution of an indirect (also referred to as non-algebraic or nonlinear) eigenvalue problem is the "nal step of a variety of well established numerical methods for guided wave and resonator analysis. It amounts to a numerical search for the singularities of a matrix valued function of wave numbe
Examples of embedded eigenvalues for problems in acoustic waveguides
โ Scribed by M. D. Groves
- Publisher
- John Wiley and Sons
- Year
- 1998
- Tongue
- English
- Weight
- 248 KB
- Volume
- 21
- Category
- Article
- ISSN
- 0170-4214
No coin nor oath required. For personal study only.
โฆ Synopsis
Communicated by P. Werner
This short article discusses the spectrum of the Neumann Laplacian in the infinite domain L1L, n*2 created by inserting a compact obstacle P into the uniform cylinder "( !R, R); . The main result is the existence of at least one embedded eigenvalue when P is an (n!2)-dimensional surface whose unit normal is parallel to at each point of P. The special case when P is symmetric about +0,; is also treated. It is shown that there is at least one symmetric eigenvector and, when P is sufficiently long, at least one antisymmetric eigenvector.
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