Abstract:
:This paper presents a study on the wave surfaces of anisotropic solids. In addition to the classical and real rays, which are defined by the normal to the slowness surfaces, it is obtained complex rays, which are associated to specific inhomogeneous plane waves. Referring to the complex Christoffel's equation and to the Fermat's principle, an intrinsic equation can be associated to these complex rays. Limiting the study to principal planes and plotting the associated complex wave surfaces, it can be shown that four energetic rays always exist in any directions for both quasi-isotropic and anisotropic media (even beyond the cusp). Consequently, it is always possible to define four closed wave surfaces (real or not).
journal_name
Ultrasonicsjournal_title
Ultrasonicsauthors
Deschamps M,Poncelet Odoi
10.1016/s0041-624x(02)00109-9subject
Has Abstractpub_date
2002-05-01 00:00:00pages
293-6issue
1-8eissn
0041-624Xissn
1874-9968pii
S0041-624X(02)00109-9journal_volume
40pub_type
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