Navigation Links
Silicon photonic crystals key to optical cloaking, researchers say
Date:6/25/2008

CHAMPAIGN, Ill. Now you see it, soon you might not, researchers at the University of Illinois say.

In computer simulations, the researchers have demonstrated an approximate cloaking effect created by concentric rings of silicon photonic crystals. The mathematical proof brings scientists a step closer to a practical solution for optical cloaking.

"This is much more than a theoretical exercise," said Harley Johnson, a Cannon Faculty Scholar and professor of mechanical science and engineering at Illinois. "An optical cloaking device is almost within reach."

In October 2006, an invisibility cloak operating in the microwave region of the electromagnetic spectrum was reported by researchers at Duke University, Imperial College in London, and Sensor Metrix in San Diego. In their experimental demonstration, microwave cloaking was achieved through a thin coating containing an array of tiny metallic structures called ring resonators.

To perform the same feat at much smaller wavelengths in the visible portion of the spectrum, however, would require ring resonators smaller than can be made with current technology, Johnson said. In addition, because metallic particles would absorb some of the incident light, the cloaking effect would be incomplete. Faintly outlined in the shape of the container, some of the background objects would appear dimmer than the rest.

To avoid these problems, postdoctoral research associate Dong Xiao came up with the idea of using a coating of concentric rings of silicon photonic crystals. The width and spacing of the rings can be tailored for specific wavelengths of light.

"When light of the correct wavelength strikes the coating, the light bends around the container and continues on its way, like water flowing around a rock," Xiao said. "An observer sees what is behind the container, as though it isn't there. Both the container and its contents are invisible."

Currently simulated in two dimensions, the cloaking concept could be extended to three dimensions, Xiao said, by replacing the concentric rings with spherical shells of silicon, separated by air or some other dielectric.

The researchers' optical cloaking technique is not perfect, however. "The wave fronts are slightly perturbed as they pass around the container," said Johnson, who also is affiliated with the university's Beckman Institute and the Frederick Seitz Materials Research Laboratory. "Because the wave fronts don't match exactly, we refer to the technique as 'approximate' cloaking."


'/>"/>

Contact: James E. Kloeppel
kloeppel@uiuc.edu
217-244-1073
University of Illinois at Urbana-Champaign
Source:Eurekalert

Related biology technology :

1. Nanotube forests grown on silicon chips for future computers, electronics
2. Worlds most complex silicon phased-array chip developed at UC-San Diego
3. Align Technology, Inc. Ranked 23rd in Deloittes Technology Fast 50 Program for Silicon Valley Scientific & Medical Equipment, and Bio-Technology Companies
4. Job-related stress: NIST demonstrates fatigue effects in silicon
5. Move over, silicon: Advances pave way for powerful carbon-based electronics
6. UDs Appelbaum wins NSF Career Award for research on silicon spintronics
7. UCT Specialties (Formerly Petrarch) Announces the Release of Their New Product Guides for Silanes, Silicones, Platinum Catalyst and Glass Coatings
8. UM physicists show electrons can travel over 100 times faster in graphene than in silicon
9. Foldable and stretchable, silicon circuits conform to many shapes
10. The future of computing -- carbon nanotubes and superconductors to replace the silicon chip
11. Bluestar Silicones Introduces Three New Soft and Durable Liquid Silicone Rubber Products
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/28/2017)... ... April 28, 2017 , ... While things have been quiet for ... company and provide a new outlook for the future. As a continued effort ... management with the retirement of Mr. Siegel as CEO. With the new adjustments in ...
(Date:4/27/2017)... ... April 27, 2017 , ... ... digital pathology, today announced their digital pathology technology has the potential to eliminate ... five medical centers in The Netherlands as part of the 2017 ISBI ...
(Date:4/27/2017)... ... April 27, 2017 , ... During the course ... how testing for 1,25-Dihydroxyvitamin D can enhance clinical practice. Participants will learn the ... dihydroxyvitamin D. , Dr. Gregory Plotnikoff, senior consultant with Minnesota Personalized Medicine, will ...
(Date:4/27/2017)... ... 27, 2017 , ... The Council for Agricultural Science and ... Lusk, a consummate communicator who promotes agricultural science and technology in the public ... explains how innovation and growth in agriculture are critical for food security and ...
Breaking Biology Technology:
(Date:4/11/2017)... Florida , April 11, 2017 ... a security technology company, announces the appointment of independent Directors ... Bendheim to its Board of Directors, furthering the company,s ... ... of NXT-ID, we look forward to their guidance and benefiting ...
(Date:4/5/2017)... 2017  The Allen Institute for Cell Science today ... one-of-a-kind portal and dynamic digital window into the human ... first application of deep learning to create predictive models ... and a growing suite of powerful tools. The Allen ... future publicly available resources created and shared by the ...
(Date:4/5/2017)... KEY FINDINGS The global market ... CAGR of 25.76% during the forecast period of 2017-2025. ... for the growth of the stem cell market. ... MARKET INSIGHTS The global stem cell market is segmented ... The stem cell market of the product is segmented ...
Breaking Biology News(10 mins):