Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists Twist Sound with Metamaterials

26.02.2014

The World's First Acoustic Field Rotator, Described in Applied Physics Letters, May Help to Improve the Imaging Capabilities of Medical Ultrasound Devices

A Chinese-U.S. research team is exploring the use of metamaterials -- artificial materials engineered to have exotic properties not found in nature -- to create devices that manipulate sound in versatile and unprecedented ways.


J.Cheng/Nanjing University

3-D schematic of an designed acoustic field rotator, described in the journal Applied Physics Letters.

In the journal Applied Physics Letters, the team reports a simple design for a device, called an acoustic field rotator, which can twist wave fronts inside it so that they appear to be propagating from another direction.

"Numerous research efforts have centered on metamaterial-based devices with fascinating wave-control capabilities such as invisibility or illusion cloaks," said Jian-chun Cheng, a professor at the Institute of Acoustics, in the Department of Physics at Nanjing University. "An acoustic field rotator, however, which can be [considered] a special kind of illusion cloak with the capability of making an object acoustically appear like a rotated one, doesn't exist yet."

Field rotators for electromagnetic waves and liquid waves have already been demonstrated and show promise in their respective areas, but "another important type of classical wave, an acoustic wave, is a much more familiar part of our daily lives and could find applications in a variety of situations," Cheng noted.

Cheng and colleagues designed what they believe to be the first feasible acoustic rotator model and also fabricated a prototype to validate it.

"We were surprised to discover that by using metamaterials, acoustic waves can be rotated in a manner similar to their electromagnetic or liquid wave counterparts -- so sound has finally joined the club," Cheng said.

Another surprise the team discovered was that acoustic and electromagnetic rotators can be designed based on the same principles. In this case, the researchers used anisotropic metamaterials, which possess physical properties that differ along different directions.

"It's much easier to implement highly anisotropic acoustic metamaterials than electromagnetic ones, and an acoustic rotator may provide even better performance than its [electromagnetic] counterparts," said Cheng.

The team hopes their acoustic rotator, with its ability to freely manipulate acoustic wavefronts, will improve the operation of devices like medical ultrasound machines, which require the precise control of acoustic waves. The ability to rotate the sound waves could improve the contrast of ultrasound devices and allow them to image damaged tissue or diagnose diseases in ways they currently cannot. This is significant because ultrasound devices may be cheaper than other imaging modalities and do not use X-rays.

What's ahead for the team now that they've shown the possibility of building an acoustic rotator by exploiting acoustic metamaterials? "We've fabricated the simplest proof-of-concept device, which at this point can't serve as a mature and practical device, so it's worth further improvement and optimization," said Cheng.

In the future, acoustic rotators could "serve as useful building blocks for constructing more complex structures with richer acoustic manipulation functionalities, if properly combined with other kinds of components," he added.

The article, "Broadband field rotator based on acoustic metamaterials" by Xue Jiang, Bin Liang, Xin-ye Zou, Lei-lei Yin, and Jian-chun Cheng appears in the journal Applied Physics Letters (DOI: 10.1063/1.4866333). The article will be published online on February 25, 2014. After that date, it can be accessed at: http://tinyurl.com/pv78pok

The authors of this paper are affiliated with Nanjing University, the Chinese Academy of Sciences and the University of Illinois at Urbana-Champaign.

ABOUT THE JOURNAL
Applied Physics Letters features concise, rapid reports on significant new findings in applied physics. The journal covers new experimental and theoretical research on applications of physics phenomena related to all branches of science, engineering, and modern technology. See: http://apl.aip.org

Jason Socrates Bardi | newswise

Further reports about: AIP Sound acoustic anisotropic electromagnetic waves metamaterials properties waves

More articles from Physics and Astronomy:

nachricht Theory of the strong interaction verified
27.03.2015 | Forschungszentrum Juelich

nachricht Dark matter even darker than once thought
27.03.2015 | ESA/Hubble Information Centre

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Experiment Provides the Best Look Yet at 'Warm Dense Matter' at Cores of Giant Planets

In an experiment at the Department of Energy's SLAC National Accelerator Laboratory, scientists precisely measured the temperature and structure of aluminum as...

Im Focus: Energy-autonomous and wireless monitoring protects marine gearboxes

The IPH presents a solution at HANNOVER MESSE 2015 to make ship traffic more reliable while decreasing the maintenance costs at the same time. In cooperation with project partners, the research institute from Hannover, Germany, has developed a sensor system which continuously monitors the condition of the marine gearbox, thus preventing breakdowns. Special feature: the monitoring system works wirelessly and energy-autonomously. The required electrical power is generated where it is needed – directly at the sensor.

As well as cars need to be certified regularly (in Germany by the TÜV – Technical Inspection Association), ships need to be inspected – if the powertrain stops...

Im Focus: 3-D satellite, GPS earthquake maps isolate impacts in real time

Method produced by UI researcher could improve reaction time to deadly, expensive quakes

When an earthquake hits, the faster first responders can get to an impacted area, the more likely infrastructure--and lives--can be saved.

Im Focus: Atlantic Ocean overturning found to slow down already today

The Atlantic overturning is one of Earth’s most important heat transport systems, pumping warm water northwards and cold water southwards. Also known as the Gulf Stream system, it is responsible for the mild climate in northwestern Europe. 

Scientists now found evidence for a slowdown of the overturning – multiple lines of observation suggest that in recent decades, the current system has been...

Im Focus: Robot inspects concrete garage floors and bridge roadways for damage

Because they are regularly subjected to heavy vehicle traffic, emissions, moisture and salt, above- and underground parking garages, as well as bridges, frequently experience large areas of corrosion. Most inspection systems to date have only been capable of inspecting smaller surface areas.

From April 13 to April 17 at the Hannover Messe (hall 2, exhibit booth C16), engineers from the Fraunhofer Institute for Nondestructive Testing IZFP will be...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

World Conference On Regenerative Medicine 2015: Registration And Abstract Submission Now Open

25.03.2015 | Event News

University presidents from all over the world meet in Hamburg

19.03.2015 | Event News

10. CeBiTec Symposium zum Big Data-Problem

17.03.2015 | Event News

 
Latest News

Two Most Destructive Termite Species Forming Superswarms in South Florida

27.03.2015 | Agricultural and Forestry Science

ORNL-Led Team Demonstrates Desalination with Nanoporous Graphene Membrane

27.03.2015 | Materials Sciences

Coorong Fish Hedge Their Bets for Survival

27.03.2015 | Ecology, The Environment and Conservation

VideoLinks
B2B-VideoLinks
More VideoLinks >>>