Experimental and theoretical study of reflection and coherent thermal emission by a SiC grating supporting a surface-phonon polariton
Résumé
Polarized directional reflectivity and emissivity of a SiC one-dimensional grating are studied. Measurements and calculations are performed between 10 and 11.5 m where the real part of the permittivity of SiC is negative. Pronounced dips due to surface-phonon polariton excitations are observed in the reflectivity spectra in p polarization. Thermal emission displays peaks in the same directions and at the same particular frequencies. A comparison between theory and experiments shows a good agreement for both cases. The dispersion relation is obtained theoretically and experimentally. Finally, we discuss the spatial coherence of the mono-chromatic thermal emission. Indeed, it is shown that the existence of peaks of the emitted-monochromatic radiation, in particular angular directions, implies that, due to surface waves, the thermally excited field is partially spatially coherent along the interface.
Domaines
Optique [physics.optics]Origine | Fichiers éditeurs autorisés sur une archive ouverte |
---|
Loading...