Nanotechnology Now

Our NanoNews Digest Sponsors



Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > KIT Researchers Transfer the Concept of an Optical Invisibility Cloak to Sound Waves

“Circling“ around the silent center: Design (top) and intermediate step of production (bottom) of the elastic invisibility cloak. (Graphics: AP, KIT)
“Circling“ around the silent center: Design (top) and intermediate step of production (bottom) of the elastic invisibility cloak.

(Graphics: AP, KIT)

Abstract:
Progress of metamaterials in nanotechnologies has made the invisibility cloak, a subject of mythology and science fiction, become reality: Light waves can be guided around an object to be hidden, in such a way that this object appears to be non-existent. This concept applied to electromagnetic light waves may also be transferred to other types of waves, such as sound waves. Researchers from Karlsruhe Institute of Technology (KIT) have now succeeded in demonstrating for the first time an invisibility cloak for elastic waves. Such waves also occur in strings of a guitar or drum membranes.

KIT Researchers Transfer the Concept of an Optical Invisibility Cloak to Sound Waves

Germany | Posted on December 20th, 2011

It is as if Harry Potter had a cloak that also makes him unhearable. "Maybe a place of peace and quiet in the Christmas season," say the KIT researchers, who succeeded in transferring the concepts underlying the optical invisibility cloak to acoustic waves in a plate.

"The key to controlling waves is to specifically influence their local speed as a function of the ‘running direction' of the wave," says Dr. Nicolas Stenger from the Institute of Applied Physics (AP). In his experiment, he used a smartly microstructured material composed of two polymers: A soft and a hard plastic in a thin plate. The vibrations of this plate are in the range of acoustic frequencies, that is some 100 Hz, and can be observed directly from above. The scientists found that the sound waves are guided around a circular area in the millimeter-thin plate in such a way that vibrations can neither enter nor leave this area. "Contrary to other known noise protection measures, the sound waves are neither absorbed nor reflected," says Professor Martin Wegener from the Institute of Applied Physics and coordinator of the DFG Center for Functional Nanostructures (CFN) at KIT. "It is as if nothing was there." Both physicists and Professor Martin Wilhelm from the KIT Institute for Chemical Technology and Polymer Chemistry have now published their results in the journal "Physical Review Letters."

The scientists explain their idea by the following story: A city, in the shape of a circle, suffers from noisy car traffic through its center. Finally, the mayor has the idea to introduce a speed limit for cars that drive directly towards the city: The closer the cars come to the city area, the slower they have to drive. At the same time, the mayor orders to build circular roads around the city, on which the cars are allowed to drive at higher speeds. The cars can approach the city, drive around it, and leave it in the same direction in the end. The time required corresponds to the time needed without the city. From outside, it appears as if the city was not there.

####

About Karlsruhe Institute of Technology (KIT)
Karlsruhe Institute of Technology (KIT) is a public corporation according to the legislation of the state of Baden-Württemberg. It fulfills the mission of a university and the mission of a national research center of the Helmholtz Association. KIT focuses on a knowledge triangle that links the tasks of research, teaching, and innovation.

For more information, please click here

Contacts:
Margarete Lehné
Presse, Kommunikation und Marketing
Phone: +49 721 608-48121
Fax: +49 721 608-45681
margarete.lehne at kit edu

Copyright © Karlsruhe Institute of Technology (KIT)

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 Topical Hemostatic Agent: Neutral Self-Assembling Peptide Hydrogel September 30th, 2014

Chemical interactions between silver nanoparticles and thiols: A comparison of mercaptohexanol again September 30th, 2014

A Heartbeat Away? Hybrid "Patch" Could Replace Transplants: TAU researcher harnesses gold nanoparticles to engineer novel biocompatible cardiac patch September 30th, 2014

Nanoparticles Used to Improve Quality of Bone Cement September 29th, 2014

Physics

Brookhaven Lab's National Synchrotron Light Source II Approved to Start Routine Operations: Milestone marks transition to exciting new chapter September 23rd, 2014

Toward optical chips: A promising light source for optoelectronic chips can be tuned to different frequencies September 19th, 2014

Elusive Quantum Transformations Found Near Absolute Zero: Brookhaven Lab and Stony Brook University researchers measured the quantum fluctuations behind a novel magnetic material's ultra-cold ferromagnetic phase transition September 15th, 2014

Excitonic Dark States Shed Light on TMDC Atomic Layers: Berkeley Lab Discovery Holds Promise for Nanoelectronic and Photonic Applications September 11th, 2014

Discoveries

New Topical Hemostatic Agent: Neutral Self-Assembling Peptide Hydrogel September 30th, 2014

Chemical interactions between silver nanoparticles and thiols: A comparison of mercaptohexanol again September 30th, 2014

A Heartbeat Away? Hybrid "Patch" Could Replace Transplants: TAU researcher harnesses gold nanoparticles to engineer novel biocompatible cardiac patch September 30th, 2014

Nanoparticles Used to Improve Quality of Bone Cement September 29th, 2014

Announcements

New Topical Hemostatic Agent: Neutral Self-Assembling Peptide Hydrogel September 30th, 2014

Chemical interactions between silver nanoparticles and thiols: A comparison of mercaptohexanol again September 30th, 2014

A Heartbeat Away? Hybrid "Patch" Could Replace Transplants: TAU researcher harnesses gold nanoparticles to engineer novel biocompatible cardiac patch September 30th, 2014

Nanoparticles Used to Improve Quality of Bone Cement September 29th, 2014

Military

UT Arlington researchers develop transparent nanoscintillators for radiation detection for medical safety and homeland security September 29th, 2014

'Pixel' engineered electronics have growth potential: Rice, Oak Ridge, Vanderbilt, Penn scientists lead creation of atom-scale semiconducting composites September 29th, 2014

Nanotechnology leads to better, cheaper LEDs for phones and lighting September 24th, 2014

Engineered proteins stick like glue — even in water: New adhesives based on mussel proteins could be useful for naval or medical applications September 22nd, 2014

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 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE