Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Transmission lines for nanofocusing of Infrared Light

Original publication:
M. Schnell, P. Alonso-González, F. Casanova, L. Arzubiaga, L. E. Hueso, A. Chuvilin, R. Hillenbrand
Nanofocusing of Mid-Infrared Energy with Tapered Transmission Lines 
Nature Photonics, advanced online publication, 03 April 2011.
Original publication: M. Schnell, P. Alonso-González, F. Casanova, L. Arzubiaga, L. E. Hueso, A. Chuvilin, R. Hillenbrand Nanofocusing of Mid-Infrared Energy with Tapered Transmission Lines Nature Photonics, advanced online publication, 03 April 2011.

Abstract:
A joint cooperation between three research groups at nanoGUNE (Donostia - San Sebastian, Spain) reports an innovative method to focus infrared light with tapered transmission lines to nanometer-size dimensions. This device could trigger the development of novel chemical and biological sensing tools, including ultra-small infrared spectrometers and lab-on-a-chip integrated biosensors.

Transmission lines for nanofocusing of Infrared Light

San Sebastian, Spain | Posted on April 5th, 2011

In conventional optical instruments, light cannot be focused to spot sizes smaller than half the wavelength because of diffraction effects. An important approach to beat this diffraction limit is based on optical antennas, their name being an allusion to their radiofrequency counterparts. They have the ability to concentrate (focus) light to tiny spots of nanometer-scale dimensions, which are orders of magnitude smaller than what conventional lenses can achieve. Tiny objects such as molecules or semiconductor nanoparticles that are placed into these so-called "hot spots" of the antenna can efficiently interact with light. Thus, optical antennas boost single molecule spectroscopy or the sensitivity of optical detectors. However, the hot spot is bound to the antenna structure, which limits flexibility in designing nanooptical circuits.

The experiments conducted at nanoGUNE now show that infrared light can be transported and nanofocused with miniature transmission lines, consisting of two closely spaced metal nanowires. While lenses and mirrors manipulate light in its form of a free-space propagating wave, transmission lines guide the infrared light in form of a tightly bound surface wave (Nature Photonics, 03 April 11).

The researchers at nanoGUNE adapted the concept of classic transmission lines to the infrared frequency range. Transmission lines are specialized cables for carrying for example radio frequency signals. A simple form consists of two metal wires running closely in parallel, also called ladder line. This structure was widely used in former times for connecting the radio receiver or television set to the rooftop antenna. Applied at MHz frequencies, where typical wavelengths are in the range of centimeters to several meters, it is a prime example for transport of energy in waveguides of strongly subwavelength-scale diameter.

In their experiments, the researchers demonstrated that infrared light can be transported in the same way, by scaling down the size of the transmission lines to below 1 micrometer (left panel of the figure). To that end, they fabricated two metal nanowires connected to an infrared antenna. The antenna captures infrared light and converts it into a propagating surface wave traveling along the transmission line. By gradually reducing the width of the transmission line ("tapering"), the researchers demonstrate that the infrared surface wave is compressed to a tiny spot at the taper apex with a diameter of only 60 nm (see right panel of the figure). This tiny spot is 150 times smaller than the free-space wavelength, emphasizing the extreme subwavelength-scale focus achieved in the experiments. The researchers applied their recently introduced near-field microscopy technique (Schnell et al., Nano Lett. 10 3524 (2010)) to map the different electrical field components of the infrared focus with nanoscale resolution.

Nanofocusing of infrared light with transmission lines has important implications in spectroscopy and sensing applications. Connecting a transmission line to the antenna, the infrared light captured by the nanoantenna can be transported over significant distances and nanofocused in a remote place. "This opens new pathways for the development of infrared nanocircuits" says Rainer Hillenbrand leader of the Nanooptics Group at the nanoscience institute nanoGUNE. "It is amazing that the classical radiofrequency concepts still work at infrared frequencies. That is 30 THz!" adds Martin Schnell who performed the experiments.

"Near-field optical microscopy techniques urgently seek for new ways to confine light down to the nanometer scale" explains Rainer Hillenbrand. "The concept of tapered transmission lines is a promising way to do achieve this. Acting as an ultra-small torch, it conducts infrared light exactly to the spot under analysis" says Martin Schnell.

Original publication:
M. Schnell, P. Alonso-González, F. Casanova, L. Arzubiaga, L. E. Hueso, A. Chuvilin, R. Hillenbrand
Nanofocusing of Mid-Infrared Energy with Tapered Transmission Lines
Nature Photonics, advanced online publication, 03 April 2011.

####

About nanoGUNE
The CIC nanoGUNE Consolider, nanoGUNE in short, is the Basque nanoscience and nanotechnology research center, inaugurated in 2009 in Donostia – San Sebastián, Spain. The collaborative environment at the center has been one of the keys to the success of the idea. The fabrication of the transmission lines was carried out by members of the Nanodevices Group and the TEM Laboratory, while the infrared transport and focusing functionality was designed and verified in the Nanooptics Group. “It’s great having the tools and expertise you need in the labs right next to yours” says Hillenbrand.

Contacts:
Oihane Lakar Iraizoz
0034-943-363040

Copyright © AlphaGalileo

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

New nanomaterial maintains conductivity in three dimensions: International team seamlessly bonds CNTs and graphene September 5th, 2015

Multi-million pound project to use nanotechnology to improve safety September 4th, 2015

Magnetic wormhole connecting 2 regions of space created for the first time: The device could have applications in medicine, opening up ways to make MRIs more comfortable for patients September 4th, 2015

Tongfang Global and QD Vision Partner to Bring Wide Color Gamut to Global Television Lines: Color IQTM quantum dots help boost company’s focus on superior color reproduction September 3rd, 2015

Lab-on-a-chip

Bionic liver micro-organs explain off-target toxicity of acetaminophen (Tylenol): Israeli-German partnership aims to replace animal experiments with advanced liver-on-chip devices August 17th, 2015

New optical chip lights up the race for quantum computer August 14th, 2015

Smart hydrogel coating creates 'stick-slip' control of capillary action July 27th, 2015

Miniature Technology, Large-Scale Impact: Winner of the 2015 Lindros Award for translational medicine, Kjeld Janssen is pushing the boundaries of the emerging lab-on-a-chip technology July 7th, 2015

Announcements

New nanomaterial maintains conductivity in three dimensions: International team seamlessly bonds CNTs and graphene September 5th, 2015

Multi-million pound project to use nanotechnology to improve safety September 4th, 2015

Magnetic wormhole connecting 2 regions of space created for the first time: The device could have applications in medicine, opening up ways to make MRIs more comfortable for patients September 4th, 2015

Making fuel from light: Argonne research sheds light on photosynthesis and creation of solar fuel September 3rd, 2015

Photonics/Optics/Lasers

Reversible Writing with Light: Self-assembling nanoparticles take their cues from their surroundings September 3rd, 2015

A marine creature's magic trick explained: Crystal structures on the sea sapphire's back appear differently depending on the angle of reflection September 2nd, 2015

Scientists 'squeeze' light one particle at a time: A team of scientists have measured a bizarre effect in quantum physics, in which individual particles of light are said to have been 'squeezed' -- an achievement which at least one textbook had written off as hopeless September 1st, 2015

Nanotechnology that will impact the Security & Defense sectors to be discussed at NanoSD2015 conference August 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







Car Brands
Buy website traffic