Light and sound fire scientists' imaginations

December 12, 2013

HOUSTON - (Dec. 12, 2013) - Strategies to manipulate light and sound go back to the first spherical glass bead and the pounding of the first hollow log. But their full potential is only just becoming apparent, according to a review by materials scientists at Rice University and their colleagues.

New abilities to corral light and sound from the macroscale to the nanoscale with structured polymers could deliver profound changes in the way we live, said materials scientist Edwin "Ned" Thomas, the William and Stephanie Sick Dean of the George R. Brown School of Engineering at Rice. Such advanced materials could not only revolutionize computing and sensing technology but could also bring about new strategies for soundproofing buildings and cars, managing heat and cold and making submarines invisible to sonar, he said.

"And then there's the invisibility cloak, like in 'Harry Potter,'" Thomas said. "That's a special effect in the movie, but we're getting to the point where we can do it for real."

Thomas and Rice research scientist Jae-Hwang Lee are primary authors of the comprehensive summary of research into photonics (light), phononics (sound) and hybrid phoXonics (light and sound) materials. The chapter-length, open-access review titled "Ordered Polymer Structures for the Engineering of Photons and Phonons" was published online today by the journal Advanced Materials.

Manipulating light has been around for a long time, said Thomas, who specializes in polymeric materials. "Photonics made a significant advance by showing we can confine light and make it go where we want it to go," he said. "Now we're molding the flow of elastic waves - of which sound is a subset - in similar ways. And there's growing emphasis on devices that handle light and elastic waves simultaneously to do cool things - not with one or the other, but with both."

The review follows by four years a book on the topic by Thomas and Massachusetts Institute of Technology (MIT) colleague Martin Maldovan. "There have been a lot of advances since then," Thomas said. "When we were asked by the journal to do this, I told the editor I didn't think it was going to be a short review."

He was right. The review cites more than 400 papers as it details dozens of theories and suggests techniques for the manufacture of devices, along with a few original ideas "we wanted in the literature," Thomas said.

The review primarily deals with photonics and its close relative, plasmonics, a topic of great interest at Rice's Laboratory for Nanophotonics. But the last third of the paper dives into phononics. Treating sound waves somewhat like light waves is a fairly recent approach in materials science, but research into the nanoscale manipulation of sound using materials with periodic mechanical impedance is rising quickly, Thomas said.

"Phononics for sound is probably even more practical than photonics for light, in a way," he said. "Everybody wants to control sound: either get rid of it, enhance it or filter certain frequencies. And this field's moving fast."

The review shows the breadth of research into fashioning polymers that create band gaps for sound and light similar to those that give semiconductors their unique electronic properties. A band gap can be tuned by patterning the materials via a number of techniques to allow only particular frequencies of sound or light to pass through while blocking all others.

The ability to control such properties on the micron scale could make a soundproofing material nearly as thin as a layer of paint, Thomas said. In fact, for some applications it could direct rather than absorb: These thin materials would guide sound waves around an object and emit them on the far side.

That would make submarines effectively invisible, he said. "Normal materials that essentially absorb sound are thick and big. Just look inside any concert hall. With phononics we should be able to make metamaterials that are just as effective but in a smaller form factor. You can't coat a submarine with a 300-foot-thick membrane over the entire hull. But if you could coat it with something half-a-centimeter thick, game on."

Thomas thinks scientists are on the brink of a materials revolution, and the new paper presents plenty of evidence. "This excites me because we're not just making incremental improvements to known properties; usually, materials science is about the material and the structure and whatever makes sense for the application. But we're flipping that. The boundaries we know about don't contain all the solutions. There are things beyond our mindset that contain answers to questions we haven't even imagined.

"The people I work with - the physicists, electrical engineers, materials scientists, chemists - they're all excited about this because they know there are probably way more surprises in the future," he said.
-end-
Co-authors are Rice postdoctoral researchers Seog-Jin Jeon and Ori Stein; Yale University postdoctoral researcher Jonathan Singer; Cheong Yang Koh, a researcher at DSO National Laboratories in Singapore; and Maldovan, a research scientist at MIT.

The Asian Office of Aerospace Research and Development through the Defense Thread Reduction Agency and the U.S. Army Research Office through the Institute of Soldier Nanotechnology at MIT supported the research.

Read the paper athttp://onlinelibrary.wiley.com/doi/10.1002/adma.201303456/abstract

This news release can be found online at http://news.rice.edu/2013/12/12/light-and-sound-fire-scientists-imaginations/

Follow Rice News and Media Relations via Twitter @RiceUNews

Related Materials:

Sound Ideas: http://tinyurl.com/nobf9ao

Edwin "Ned" Thomas: http://memsweb.rice.edu/thomas/

Images for download:

http://news.rice.edu/wp-content/uploads/2012/10/1102_STRAIN-2-WEB.jpg

Rice University scientists Ned Thomas (left), dean of the George R. Brown School of Engineering, and Jae-Hwang Lee are the primary authors of a new review of photonic, phononic and phoXonics research in the journal Advanced Materials. (Credit: Tommy LaVergne/Rice University)

Located on a 300-acre forested campus in Houston, Rice University is consistently ranked among the nation's top 20 universities by U.S. News & World Report. Rice has highly respected schools of Architecture, Business, Continuing Studies, Engineering, Humanities, Music, Natural Sciences and Social Sciences and is home to the Baker Institute for Public Policy. With 3,708 undergraduates and 2,374 graduate students, Rice's undergraduate student-to-faculty ratio is 6-to-1. Its residential college system builds close-knit communities and lifelong friendships, just one reason why Rice has been ranked No. 1 for best quality of life multiple times by the Princeton Review and No. 2 for "best value" among private universities by Kiplinger's Personal Finance. To read "What they're saying about Rice," go to http://tinyurl.com/AboutRiceU.

Rice University

Related Nanoscale Articles from Brightsurf:

Nanoscale machines convert light into work
Researchers have developed a tiny new machine that converts laser light into work.

Discovery will allow more sophisticated work at nanoscale
The movement of fluids through small capillaries and channels is crucial for processes ranging from blood flow through the brain to power generation and electronic cooling systems, but that movement often stops when the channel is smaller than 10 nanometers.

Valley-Hall nanoscale lasers
Topological photonics allows the creation of new states of light.

Dynamics of DNA replication revealed at the nanoscale
Using super-resolution technology a University of Technology Sydney led team has directly visualised the process of DNA replication in single human cells.

House cleaning on the nanoscale
A team of scientists at Friedrich-Alexander Universität Erlangen-Nürnberg (FAU) has developed a novel mechanical cleaning method for surfaces on the nanoscale.

As electronics shrink to nanoscale, will they still be good as gold?
As circuit interconnects shrink to nanoscale, will the pressure caused by thermal expansion when current flows through wires cause gold to behave more like a liquid than a solid -- making nanoelectronics unreliable?

A joint venture at the nanoscale
Scientists at Argonne National Laboratory report fabricating and testing a superconducting nanowire device applicable to high-speed photon counting.

Bending diamond at the nanoscale
A team of Australian scientists has discovered diamond can be bent and deformed, at the nanoscale at least.

Creating a nanoscale on-off switch for heat
Researchers create a polymer thermal regulator that can quickly transform from a conductor to an insulator, and back again.

Magnetic tuning at the nanoscale
Physicists from the German research center Helmholtz-Zentrum Dresden-Rossendorf (HZDR) are working to produce engineered magnetic nanostructures and to tailor material properties at the nanoscale.

Read More: Nanoscale News and Nanoscale Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.