Subwavelength focusing with a multilayered Fabry-Perot structure at optical frequencies
2007 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 75, no 4, 045103- p.Article in journal (Refereed) Published
The Fabry-Perot resonance effect is studied in order to achieve subwavelength imaging at a far distance (e.g., about 10 wavelengths) from the source at optical frequencies. Two different structures (with matched and mismatched impedances) of alternative metal and air layers are considered first at a relatively short distance (e.g., about one wavelength) from the source. It is found that the impedance match is not necessary for subwavelength focusing since the Fabry-Perot resonance effect is utilized here. An appropriate period is chosen so that the Fabry-Perot resonance occurs in an evanescent regime, and consequently the evanescent waves near the Fabry-Perot resonance peak are amplified. With such a mechanism, a super lens with a resolution of about λ0/30 (λ0 is the wavelength in the air), acceptable sidelobes and a larger displacement range (when the thickness of the period is within such a displacement range, subwavelength focusing with acceptable sidelobes can be achieved) is designed. Subwavelength focusing (with a spotsize of λ0/12) at a distance far away from the source is also realized in the presence of some material loss.
Place, publisher, year, edition, pages
2007. Vol. 75, no 4, 045103- p.
PERFECT LENS, NEAR-FIELD
Other Electrical Engineering, Electronic Engineering, Information Engineering
IdentifiersURN: urn:nbn:se:kth:diva-12461DOI: 10.1103/PhysRevB.75.045103ISI: 000243895600020ScopusID: 2-s2.0-33846352516OAI: oai:DiVA.org:kth-12461DiVA: diva2:312921