Optimized grating as an ultra-narrow band absorber or plasmonic sensor
2014 (English)In: Optics Letters, ISSN 0146-9592, E-ISSN 1539-4794, Vol. 39, no 5, 1137-1140 p.Article in journal (Refereed) Published
Lamellar gratings are investigated via temporal coupled-mode theory and numerical simulations. Total absorption can be achieved by an optimized grating with shallow grooves under normal incidence and the full width at half-maximum (FWHM) is only 0.4 nm. For certain wavelengths, the structure shows high absorption only within an ultra-narrow angle, which suggests that it can be used as a highly directional thermal emitter according to Kirchhoff's law. Besides, the resonant wavelength is sensitive to the refractive index of the environmental dielectric. The large sensitivity (1400 nm/RIU) and simultaneous small FWHM result in a huge figure-of-merit of 2300/RIU, which enables the structure to have great potential in plasmonic sensing.
Place, publisher, year, edition, pages
2014. Vol. 39, no 5, 1137-1140 p.
Light-Absorption, Thermal Sources, Resonance, Metals
Engineering and Technology
IdentifiersURN: urn:nbn:se:kth:diva-143699DOI: 10.1364/OL.39.001137ISI: 000332233300009ScopusID: 2-s2.0-84897397644OAI: oai:DiVA.org:kth-143699DiVA: diva2:708919
FunderSwedish Research CouncilSwedish Foundation for Strategic Research
QC 201403312014-03-312014-03-272014-03-31Bibliographically approved