ec 2 00 4 Enhanced diffraction by a rectangular grating made of a negative phase – velocity ( or negative index ) material
نویسندگان
چکیده
The diffraction of electromagnetic plane waves by a rectangular grating formed by discrete steps in the interface of a homogeneous, isotropic, linear, negative phase– velocity (negative index) material with free space is studied using the semi–analytic C method. When a nonspecular diffracted order is of the propagating type, coupling to that order is significantly larger for a negative index material than for conventional material. The computed coupling strengths reported here are in agreement with recent experiments, and illustrate the role of evanescent fields localized at the grating interface in producing this enhanced coupling. PACS: 42.25.Fx, 78.20.Ci
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Enhanced diffraction by a rectangular grating made of a negative phase-velocity (or negative index) material
The diffraction of electromagnetic plane waves by a rectangular grating formed by discrete steps in the interface of a homogeneous, isotropic, linear, negative phase-velocity (negative index) material with free space is studied using the semi-analytic C method. When a nonspecular diffracted order is of the propagating type, coupling to that order is significantly larger for a negative index mat...
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متن کامل. cl as s - ph ] 2 8 A ug 2 00 3 Restricted equivalence of paired epsilon – negative and mu – negative layers to a negative phase – velocity material ( alias left – handed material )
The time–harmonic electromagnetic responses of (a) a bilayer made of an epsilon–negative layer and a mu–negative layer, and (b) a single layer of a negative phase– velocity material are compared. Provided all layers are electrically thin, a restricted equivalence between (a) and (b) exists. The restricted equivalence depends on the linear polarization state and the transverse wavenumber. Implic...
متن کاملA ug 2 00 3 Restricted equivalence of paired epsilon – negative and mu – negative layers to a negative phase – velocity material ( alias left – handed material )
The time–harmonic electromagnetic responses of (a) a bilayer made of an epsilon–negative layer and a mu–negative layer, and (b) a single layer of a negative phase– velocity material are compared. Provided all layers are electrically thin, a restricted equivalence between (a) and (b) exists. The restricted equivalence depends on the linear polarization state and the transverse wavenumber. Implic...
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