Nanotechnology Now







Heifer International

Wikipedia Affiliate Button


DHgate

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

Mass spectrometers with optimised hydrogen pumping March 1st, 2015

Imec Demonstrates Compact Wavelength-Division Multiplexing CMOS Silicon Photonics Transceiver March 1st, 2015

onic Present breakthrough in CMOS-based Transceivers for mm-Wave Radar Systems March 1st, 2015

Graphene Shows Promise In Eradication Of Stem Cancer Cells March 1st, 2015

Possible Futures

European roadmap for graphene science and technology published February 25th, 2015

Quantum research past, present and future for discussion at AAAS February 16th, 2015

World’s first compact rotary 3D printer-cum-scanner unveiled at AAAS by NTU Singapore start-up: With production funded by crowdsourcing, the first unit will be delivered to the United States in March February 16th, 2015

Nanotechnology Electric Vehicle (EV) Market Analysis Report 2015: According to Radiant Insights, Inc February 13th, 2015

Academic/Education

NanoTecNexus Launches New App for Learning About Nanotechnology—STEM Education Project Spearheaded by Interns February 26th, 2015

SUNY Poly CNSE Researchers and Corporate Partners to Present Forty Papers at Globally Recognized Lithography Conference: SUNY Poly CNSE Research Group Awarded Both ‘Best Research Paper’ and ‘Best Research Poster’ at SPIE Advanced Lithography 2015 forum February 25th, 2015

KIT Increases Commitment in Asia: DAAD Funds Two New Projects: Strategic Partnerships with Chinese Universities and Communi-cation Technologies Network February 22nd, 2015

Minus K Technology Announces Its 2015 Vibration Isolator Educational Giveaway to U.S. Colleges and Universities February 18th, 2015

Sensors

Penn researchers develop new technique for making molybdenum disulfide: Extra control over monolayer material with advantages over graphene February 19th, 2015

Researchers build atomically thin gas and chemical sensors: Sensors made of molybdenum disulfide are small, thin and have a high level of selectivity when detecting gases and chemicals February 19th, 2015

Production of Biosensor in Iran to Detect Oxalic Acid February 18th, 2015

Improved fire detection with new ultra-sensitive, ultraviolet light sensor February 17th, 2015

Discoveries

Imec, Holst Centre and Renesas Present World’s Lowest Power 2.4GHz Radio Chip for Bluetooth Low Energy March 1st, 2015

Imec, Murata, and Huawei Introduce Breakthrough Solution for TX-to-RX Isolation in Reconfigurable, Multiband Front-End Modules for Mobile Phones: Electrical-Balance Duplexers Pave the Way to Integrated Solution for TX-to-RX Isolation March 1st, 2015

Imec Demonstrates Compact Wavelength-Division Multiplexing CMOS Silicon Photonics Transceiver March 1st, 2015

Graphene Shows Promise In Eradication Of Stem Cancer Cells March 1st, 2015

Announcements

Imec, Murata, and Huawei Introduce Breakthrough Solution for TX-to-RX Isolation in Reconfigurable, Multiband Front-End Modules for Mobile Phones: Electrical-Balance Duplexers Pave the Way to Integrated Solution for TX-to-RX Isolation March 1st, 2015

Imec Demonstrates Compact Wavelength-Division Multiplexing CMOS Silicon Photonics Transceiver March 1st, 2015

onic Present breakthrough in CMOS-based Transceivers for mm-Wave Radar Systems March 1st, 2015

Graphene Shows Promise In Eradication Of Stem Cancer Cells March 1st, 2015

Photonics/Optics/Lasers

Imec Demonstrates Compact Wavelength-Division Multiplexing CMOS Silicon Photonics Transceiver March 1st, 2015

Leti to Offer Updates on Silicon Photonics Successes at OFC in LA February 27th, 2015

Rice's Stephan Link honored for nanoscience research: The Welch Foundation honors ‘rising star’ with $100,000 Hackerman Award February 26th, 2015

Maximum Precision in 3D Printing: New complete solution makes additive manufacturing standard for microfabrication February 26th, 2015

Research partnerships

Imec, Holst Centre and Renesas Present World’s Lowest Power 2.4GHz Radio Chip for Bluetooth Low Energy March 1st, 2015

Imec, Murata, and Huawei Introduce Breakthrough Solution for TX-to-RX Isolation in Reconfigurable, Multiband Front-End Modules for Mobile Phones: Electrical-Balance Duplexers Pave the Way to Integrated Solution for TX-to-RX Isolation March 1st, 2015

Imec Demonstrates Compact Wavelength-Division Multiplexing CMOS Silicon Photonics Transceiver March 1st, 2015

onic Present breakthrough in CMOS-based Transceivers for mm-Wave Radar Systems March 1st, 2015

Solar/Photovoltaic

New nanowire structure absorbs light efficiently: Dual-type nanowire arrays can be used in applications such as LEDs and solar cells February 25th, 2015

Learning by eye: Silicon micro-funnels increase the efficiency of solar cells February 25th, 2015

Magnetic nanoparticles enhance performance of solar cells X-ray study points the way to higher energy yields February 25th, 2015

Researchers enable solar cells to use more sunlight February 25th, 2015

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







© Copyright 1999-2015 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE