Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Scientists Twist Sound with Metamaterials


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:

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

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:

Jason Socrates Bardi | newswise

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

More articles from Physics and Astronomy:

nachricht Sharpening the X-ray view of the nanocosm
23.03.2018 | Changchun Institute of Optics, Fine Mechanics and Physics

nachricht Drug or duplicate?
23.03.2018 | Fraunhofer-Institut für Angewandte Festkörperphysik IAF

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: Space observation with radar to secure Germany's space infrastructure

Satellites in near-Earth orbit are at risk due to the steady increase in space debris. But their mission in the areas of telecommunications, navigation or weather forecasts is essential for society. Fraunhofer FHR therefore develops radar-based systems which allow the detection, tracking and cataloging of even the smallest particles of debris. Satellite operators who have access to our data are in a better position to plan evasive maneuvers and prevent destructive collisions. From April, 25-29 2018, Fraunhofer FHR and its partners will exhibit the complementary radar systems TIRA and GESTRA as well as the latest radar techniques for space observation across three stands at the ILA Berlin.

The "traffic situation" in space is very tense: the Earth is currently being orbited not only by countless satellites but also by a large volume of space...

Im Focus: Researchers Discover New Anti-Cancer Protein

An international team of researchers has discovered a new anti-cancer protein. The protein, called LHPP, prevents the uncontrolled proliferation of cancer cells in the liver. The researchers led by Prof. Michael N. Hall from the Biozentrum, University of Basel, report in “Nature” that LHPP can also serve as a biomarker for the diagnosis and prognosis of liver cancer.

The incidence of liver cancer, also known as hepatocellular carcinoma, is steadily increasing. In the last twenty years, the number of cases has almost doubled...

Im Focus: Researchers at Fraunhofer monitor re-entry of Chinese space station Tiangong-1

In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.

Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...

Im Focus: Alliance „OLED Licht Forum“ – Key partner for OLED lighting solutions

Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.

They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...

Im Focus: Mars' oceans formed early, possibly aided by massive volcanic eruptions

Oceans formed before Tharsis and evolved together, shaping climate history of Mars

A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

New solar solutions for sustainable buildings and cities

23.03.2018 | Event News

Virtual reality conference comes to Reutlingen

19.03.2018 | Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

Latest News

For graphite pellets, just add elbow grease

23.03.2018 | Materials Sciences

Unique communication strategy discovered in stem cell pathway controlling plant growth

23.03.2018 | Agricultural and Forestry Science

Sharpening the X-ray view of the nanocosm

23.03.2018 | Physics and Astronomy

Science & Research
Overview of more VideoLinks >>>