Regensburg 2004 – scientific programme

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HL: Halbleiterphysik

HL 2: Symposium Photonische Kristalle

HL 2.4: Talk

Monday, March 8, 2004, 11:45–12:15, H15

Diffraction Control and Enhanced Transmission through Sub-Wavelength Apertures — •Thomas W. Ebbesen — ISIS, University Louis Pasteur, 8 rue Gaspard Monge, 67000 Strasbourg, France

Periodically structured metallic films perforated with one or more sub-wavelength holes ( 150 nm) can transmit the light with an efficiency orders of magnitude larger than what theory predicts for single holes. The efficiency can even be much larger than the fractional area occupied by the hole, which means that even the light falling beside the hole emerges on the other side of the sample. This extraordinary transmission is due to the coupling of the incident light with the surface plasmons. The transmission spectrum contains peaks attributed to surface-plasmon modes that depend on both the symmetry and the 2D lattice parameter of the surface corrugation. Another fundamental problem of sub-wavelength apertures, namely optical diffraction, can also be controlled using surface plasmons. Most recently, it has been found that even isolated single subwavelength apertures (in the absence of periodic surface corrugations) can give rise to transmission peaks due the presence of localized surface plasmon modes induced at the aperture ridge. These findings have broad fundamental and practical implications and show that, with modern fabrication techniques, surface plasmons can be engineered and controlled to yield unique optical properties which could find application in high density data storage, photonic integration, near field probes, etc..