Extremely asymmetrical scattering in gratings with weak dissipation: some physical analogies

A detailed analysis of new effects related to extremely asymmetrical scattering (EAS) of bulk and guided weakly dissipating electromagnetic waves in oblique periodic gratings is presented. A very important role of the previously determined critical grating width is demonstrated for EAS in dissipative gratings. Incident and scattered wave amplitudes inside and outside the grating are analysed as functions of dissipation coefficient, grating width, grating amplitude, etc. Strong differences in the patterns of scattering in gratings that are narrower and wider than the critical width are demonstrated and discussed. Deep analogies between EAS and other resonant optical effects, such as attenuated total reflection, Fabry–Pérot interferometry, etc. are revealed and discussed. A physical interpretation of the obtained results is presented. Received: 19 February 2002 / Revised version: 28 June 2002 / Published online: 22 November 2002 RID="*" ID="*"Corresponding author. Fax: +61-7/3864-9079, E-mail: d.gramotnev@qut.edu.au