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In–out decomposition of boundary integral equations

Creagh, Stephen C.; Hamdin, Hanya Ben; Tanner, Gregor


Hanya Ben Hamdin

Professor of Applied Mathematics


We propose a reformulation of the boundary integral equations for the Helmholtz equation in a domain in terms of incoming and outgoing boundary waves. We obtain transfer operator descriptions which are exact and thus incorporate features such as diffraction and evanescent coupling; these effects are absent in the well-known semiclassical transfer operators in the sense of Bogomolny. It has long been established that transfer operators are equivalent to the boundary integral approach within semiclassical approximation. Exact treatments have been restricted to specific boundary conditions (such as Dirichlet or Neumann). The approach we propose is independent of the
boundary conditions, and in fact allows one to decouple entirely the problem of propagating waves across the interior from the problem of reflecting waves at
the boundary. As an application, we show how the decomposition may be used to calculate Goos–Haenchen shifts of ray dynamics in billiards with variable boundary conditions and for dielectric cavities.

Journal Article Type Article
Publication Date Oct 8, 2013
Journal Journalof Physics A: Mathematical and Theoretical
Electronic ISSN 1751-8113
Publisher IOP Publishing
Peer Reviewed Peer Reviewed
Volume 46
Issue 43
Article Number 435203
APA6 Citation Creagh, S. C., Hamdin, H. B., & Tanner, G. (2013). In–out decomposition of boundary integral equations. Journal of Physics A: Mathematical and Theoretical, 46(43), doi:10.1088/1751-8113/46/43/435203
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Copyright Statement Copyright information regarding this work can be found at the following address:


Creagh_In-out_decompisition.pdf (800 Kb)

Copyright Statement
Copyright information regarding this work can be found at the following address:

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