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:10/11/2017)... ... October 11, 2017 , ... ComplianceOnline’s Medical Device Summit ... 7th and 8th June 2018 in San Francisco, CA. The Summit brings together current ... several distinguished CEOs, board directors and government officials from around the world to address ...
(Date:10/11/2017)... LAGUNA HILLS, Calif. , Oct. 11, 2017  SkylineDx ... London (ICR) and University of Leeds ... to risk-stratify patients with multiple myeloma (MM), in a multi-centric ... The University of Leeds is the ... UK, and ICR will perform the testing services to include ...
(Date:10/11/2017)... (PRWEB) , ... October 11, 2017 , ... ... Administration (FDA) has granted orphan drug designation to SBT-100, its novel anti-STAT3 (Signal ... the treatment of osteosarcoma. SBT-100 is able to cross the cell membrane and ...
(Date:10/10/2017)... ... October 10, 2017 , ... For the second ... a US2020 STEM Mentoring Award. Representatives of the FirstHand program travelled to Washington, ... from US2020. , US2020’s mission is to change the trajectory of STEM education ...
Breaking Biology Technology:
(Date:4/5/2017)... 5, 2017  The Allen Institute for Cell Science ... a one-of-a-kind portal and dynamic digital window into the ... the first application of deep learning to create predictive ... lines and a growing suite of powerful tools. The ... and future publicly available resources created and shared by ...
(Date:3/30/2017)... 30, 2017  On April 6-7, 2017, Sequencing.com will ... hackathon at Microsoft,s headquarters in ... focus on developing health and wellness apps that provide ... the Genome is the first hackathon for personal ... largest companies in the genomics, tech and health industries ...
(Date:3/27/2017)... March 27, 2017  Catholic Health Services (CHS) ... Systems Society (HIMSS) Analytics for achieving Stage 6 ... sm . In addition, CHS previously earned a ... using an electronic medical record (EMR). ... level of EMR usage in an outpatient setting.  ...
Breaking Biology News(10 mins):