nt - p h / 04 06 01 9 v 1 2 J un 2 00 4 Scattering , trapped modes and guided waves in waveguides and diffraction gratings
نویسنده
چکیده
1 Scattering matrices and existence of trapped waves Systems with finitely many scattering channels are discussed in various branches of wave physics. One can mention, for instance, diffraction gratings (optics), waveguides with local perturbations (acoustics, microwave and quantum physics), etc. (few examples are shown in Fig.1). In all cases, far away from the scattering area both incident and scattered fields are sums over " modes " (specification of modes is given below). By another words, assuming some throughout enumeration of modes over all channels, any solution to the scattering problems asymptotically behaves as
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nt - p h / 02 06 01 2 v 1 3 J un 2 00 2 COHERENT STATES , ENTANGLEMENT , AND GEOMETRIC INVARIANT THEORY
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