Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Squeezed Through too Small a Hole

Transparent windows are opened in optically thick metallic films perforated with subwavelength holes by adsorbing a thin layer of molecules at the surface. Counterintuitively, transmission occurs at wavelengths at which the molecular layer absorbs strongly (in this case at 700 nm), as revealed by transmission spectra of the hole array without (black curve) and with adsorbed molecules (red).
Transparent windows are opened in optically thick metallic films perforated with subwavelength holes by adsorbing a thin layer of molecules at the surface. Counterintuitively, transmission occurs at wavelengths at which the molecular layer absorbs strongly (in this case at 700 nm), as revealed by transmission spectra of the hole array without (black curve) and with adsorbed molecules (red).

Abstract:
Photon-plasmon coupling: Dye guides light through perforated metal foil

Squeezed Through too Small a Hole

Weinheim, Germany | Posted on January 27th, 2011

Just as photons are bundles of light energy, plasmons are energy packets of plasma oscillations—oscillations of the electron density in a solid body, which are known as surface plasmons when occurring at a metal interface. Surface plasmons introduce new possibilities for the manipulation and transmission of light for applications in a variety of areas, from modern data processing to biomedical sensing. In the journal Angewandte Chemie, Thomas W. Ebbesen, James A. Hutchison, and a team from the University of Strasbourg (France) introduce an interesting new effect based on the coupling of photons and plasmons: dye molecules help light pass through holes in metal foils that are so small that conventional theory predicts the light should not actually be able to pass through at all.

According to classical aperture theory, light should not be able to pass through tiny holes when the diameter is significantly smaller than the wavelength of the light. However, as reported by Ebbesen's group over a decade ago, light transmission can be much higher than predicted for regular arrays of holes owing to the involvement of surface plasmons. In essence, light is converted into surface plasmons, and in this coupled state the photons can pass though the holes to the other side of the metal as plasmons. They can then uncouple and reappear as light.

The French team has now described another phenomenon: if dye molecules are placed directly on the perforated metal surface, they significantly increase its transparence. Contrary to expectation, the additional windows of transparency can occur at wavelengths that are strongly absorbed by the molecules. Interestingly, this also occurs if the arrangement of holes in the foil is irregular; even a single hole is enough.

The researchers propose that two complementary effects are at play. On one hand, the dye molecules in the holes generate a large index variation in the hole favoring the transmission near the absorption band. On the other, the dye molecule generates a kind of "mirror image" of its electric dipole in the metal's free electron plasma, and the dipole and mirror-image dipole interact. If the molecule then absorbs light, it is not re-emitted; instead, the light energy is completely transferred to the metal surface, where it couples with surface plasmons helping the transmission process. This combination enables the light to pass efficiently to the other side of the metal foil.

This discovery represents a new approach for making perforated metal films with tailored transmission of visible light by simply applying a dye that absorbs light with the desired wavelength, which would have application in solar energy technology, filters, and sensing. That the transient excited states of molecules have absorption properties that are very different to their ground state adds a further dynamic dimension to these films, with all-optical, ultra-fast switches another possible application.

Author: Thomas W. Ebbesen, Université de Strasbourg (France), www-isis.u-strasbg.fr/nano/start

Title: Absorption-Induced Transparency

Angewandte Chemie International Edition, Permalink dx.doi.org/10.1002/anie.201006019

####

For more information, please click here

Copyright © Angewandte Chemie International Edition

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Keeping electric car design on the right road: A closer look at the life-cycle impacts of lithium-ion batteries and proton exchange membrane fuel cells December 9th, 2016

Further improvement of qubit lifetime for quantum computers: New technique removes quasiparticles from superconducting quantum circuits December 9th, 2016

Chemical trickery corrals 'hyperactive' metal-oxide cluster December 8th, 2016

Scientists track chemical and structural evolution of catalytic nanoparticles in 3-D: Up-close, real-time, chemical-sensitive 3-D imaging offers clues for reducing cost/improving performance of catalysts for fuel-cell-powered vehicles and other applications December 8th, 2016

Possible Futures

Keeping electric car design on the right road: A closer look at the life-cycle impacts of lithium-ion batteries and proton exchange membrane fuel cells December 9th, 2016

Further improvement of qubit lifetime for quantum computers: New technique removes quasiparticles from superconducting quantum circuits December 9th, 2016

Researchers peer into atom-sized tunnels in hunt for better battery: May improve lithium ion for larger devices, like cars December 8th, 2016

Scientists track chemical and structural evolution of catalytic nanoparticles in 3-D: Up-close, real-time, chemical-sensitive 3-D imaging offers clues for reducing cost/improving performance of catalysts for fuel-cell-powered vehicles and other applications December 8th, 2016

Academic/Education

Oxford Nanoimaging report on how the Nanoimager, a desktop microscope delivering single molecule, super-resolution performance, is being applied at the MRC Centre for Molecular Bacteriology & Infection November 22nd, 2016

The University of Applied Sciences in Upper Austria uses Deben tensile stages as an integral part of their computed tomography research and testing facility October 18th, 2016

Enterprise In Space Partners with Sketchfab and 3D Hubs for NewSpace Education October 13th, 2016

New Agricultural Research Center Debuts at UCF October 12th, 2016

Sensors

Shape matters when light meets atom: Mapping the interaction of a single atom with a single photon may inform design of quantum devices December 4th, 2016

Deep insights from surface reactions: Researchers use Stampede supercomputer to study new chemical sensing methods, desalination and bacterial energy production December 2nd, 2016

Tip-assisted chemistry enables chemical reactions at femtoliter scale November 16th, 2016

'Back to the Future' inspires solar nanotech-powered clothing November 15th, 2016

Discoveries

Keeping electric car design on the right road: A closer look at the life-cycle impacts of lithium-ion batteries and proton exchange membrane fuel cells December 9th, 2016

Further improvement of qubit lifetime for quantum computers: New technique removes quasiparticles from superconducting quantum circuits December 9th, 2016

Researchers peer into atom-sized tunnels in hunt for better battery: May improve lithium ion for larger devices, like cars December 8th, 2016

Scientists track chemical and structural evolution of catalytic nanoparticles in 3-D: Up-close, real-time, chemical-sensitive 3-D imaging offers clues for reducing cost/improving performance of catalysts for fuel-cell-powered vehicles and other applications December 8th, 2016

Announcements

Keeping electric car design on the right road: A closer look at the life-cycle impacts of lithium-ion batteries and proton exchange membrane fuel cells December 9th, 2016

Further improvement of qubit lifetime for quantum computers: New technique removes quasiparticles from superconducting quantum circuits December 9th, 2016

Researchers peer into atom-sized tunnels in hunt for better battery: May improve lithium ion for larger devices, like cars December 8th, 2016

Scientists track chemical and structural evolution of catalytic nanoparticles in 3-D: Up-close, real-time, chemical-sensitive 3-D imaging offers clues for reducing cost/improving performance of catalysts for fuel-cell-powered vehicles and other applications December 8th, 2016

Photonics/Optics/Lasers

ANU invention to inspire new night-vision specs December 7th, 2016

Shape matters when light meets atom: Mapping the interaction of a single atom with a single photon may inform design of quantum devices December 4th, 2016

Controlled electron pulses November 30th, 2016

New method for analyzing crystal structure: Exotic materials called photonic crystals reveal their internal characteristics with new method November 30th, 2016

Research partnerships

Further improvement of qubit lifetime for quantum computers: New technique removes quasiparticles from superconducting quantum circuits December 9th, 2016

Researchers peer into atom-sized tunnels in hunt for better battery: May improve lithium ion for larger devices, like cars December 8th, 2016

Exotic insulator may hold clue to key mystery of modern physics: Johns Hopkins-led research shows material living between classical and quantum worlds December 8th, 2016

Deep insights from surface reactions: Researchers use Stampede supercomputer to study new chemical sensing methods, desalination and bacterial energy production December 2nd, 2016

Solar/Photovoltaic

Research Study: MetaSOLTM Shatters Solar Panel Efficiency Forecasts with Innovative New Coating: Coating Provides 1.2 Percent Absolute Enhancement to Triple Junction Solar Cells December 2nd, 2016

Throwing new light on printed organic solar cells December 1st, 2016

Physics, photosynthesis and solar cells: Researchers combine quantum physics and photosynthesis to make discovery that could lead to highly efficient, green solar cells November 30th, 2016

'Back to the Future' inspires solar nanotech-powered clothing November 15th, 2016

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project