Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Trapped light orbits within an intriguing material

17.07.2015

Light becomes trapped as it orbits within tiny granules of a crystalline material that has increasingly intrigued physicists, a team led by University of California, San Diego, physics professor Michael Fogler has found.

Hexagonal boron nitride, stacked layers of boron and nitrogen atoms arranged in a hexagonal lattice, has recently been found to bend electromagnetic energy in unusual and potentially useful ways.


Patterns of orbiting light predicted for spheroids of hexagonal boron nitride illuminated with a dipole source just above their north poles. These are false-color plots of predicted hot spots of enhanced electrical fields. Magenta lines trace the periodic orbits on the surfaces set up by particular frequencies.

Credit: Fogler group, UC San Diego

Last year Fogler and colleagues demonstrated that light could be stored within nanoscale granules of hexagonal boron nitride. Now Fogler's research group has published a new paper in the journal Nano Letters that elaborates how this trapped light behaves inside the granules.

The particles of light, called phonon polaritons, disobey standard laws of reflection as they bounce through the granules, but their movement isn't random. Polariton rays propagate along paths at fixed angles with respect to the atomic structure of the material, Folger's team reports. That can lead to interesting resonances.

"The trajectories of the trapped polariton rays are very convoluted in most instances," Fogler said. "However, at certain 'magic' frequencies they can become simple closed orbits."

When that happens "hot spots" of strongly enhanced electrical fields can emerge. Fogler's group found those can form elaborate geometric patterns in granules of spheroidal shape.

The polaritons are not only particles but also waves that form interference patterns. When overlaid on the hot contours of enhanced electrical fields, these create strikingly beautiful images.

"They resemble Fabergé eggs, the gem-encrusted treasures of the Russian tsars," Fogler observed.

Beyond creating beautiful images, their analysis illustrates the way light is stored inside the material. The patterns and the magic frequencies are determined not by the size of the spheroid but its shape, that is, the ratio of its girth to length. The analysis revealed that a single parameter determines the fixed angle along which polariton rays propagate with respect to the surface of the spheroids.

Scientists are beginning to find practical uses for materials such as hexagonal boron nitride that manipulate light in usual ways. The theory this work informed could guide the development of applications such as nanoresonators for high-resolution color filtering and spectral imaging, hyperlenses for subdiffractional imaging, or infrared photon sources.

The analysis provides a theoretical explanation for earlier observations of trapped light. Fogler and colleagues suggest several experiments that could confirm their prediction of orbiting light using advanced optical techniques, some of which are underway, Fogler said. "The experimental quest to detect orbiting polaritons has already begun."

###

Additional authors include Zhiyuan Sun, a graduate student in Fogler's research group, Angel Guttiérrez-Rubio of the Spanish National Research Council (CSIC) who contributed to the project while a visiting scholar at UC San Diego, and Dimitri Basov, a professor of physics at UC San Diego. The UC Office of the President, U.S. Department of Energy, Spanish Ministry of Economy and Competitiveness, and European Research Council supported the work.

Media Contact

Susan Brown
sdbrown@ucsd.edu
858-246-0161

 @UCSanDiego

http://www.ucsd.edu 

Susan Brown | EurekAlert!

More articles from Materials Sciences:

nachricht Move over, Superman! NIST method sees through concrete to detect early-stage corrosion
27.04.2017 | National Institute of Standards and Technology (NIST)

nachricht Control of molecular motion by metal-plated 3-D printed plastic pieces
27.04.2017 | Ecole Polytechnique Fédérale de Lausanne

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>