Featured Research

from universities, journals, and other organizations

Nanoscopic microcavities offer newfound control in light filtering: Unique nanostructure produces novel 'plasmonic halos'

Date:
February 7, 2013
Source:
Boston College
Summary:
Researchers report developing a unique nanostructure capable of filtering visible light into "plasmonic halos" of desired color output.

Boston College researchers have constructed a unique nanostructure that exploits microcavity features to filter visible light into "plasmonic halos" of selected color output. The device could have applications in areas such as biomedical plasmonics or discrete optical filtering.
Credit: Nano Letters

Using the geometric and material properties of a unique nanostructure, Boston College researchers have uncovered a novel photonic effect where surface plasmons interact with light to form "plasmonic halos" of selectable output color. The findings appear in the journal Nano Letters.

The novel nanostructure proved capable of manipulating electron waves known as surface plasmon polaritons, or SPPs, which were discovered in the 1950s but of late have garnered the attention of scientists for their potential applications in fields that include waveguiding, lasing, color filtering and printing.

The team put a layer of a polymer film on a glass substrate and then dotted the surface with holes precisely defined by a process of electron beam lithography, using the BC Integrated Sciences Nanofabrication Clean Room facility. The team next applied a layer of silver, thick enough to be nontransparent to visible light. In addition to covering the thin film on top, the silver coated the contours of the holes in the film, as well as the exposed circles of the glass substrate below. The effect produced an array of silver microcavities.

When the researchers directed light from below and through the glass substrate, light "leaking" through nanoscale gaps on the perimeters of the microcavities created SPP waves on their top surfaces. At particular wavelengths of the incident light, these waves formed modes or resonances analogous to acoustic waves on a drumhead, which in turn effectively filtered the light transmitted to the far side, accounting for the "halo" appearance, said Boston College Ferris Professor of Physics Michael Naughton, who co-authored the report with Senior Research Associate Michael J. Burns and doctoral student and lead author Fan Ye. The team's research was funded by the W. M. Keck Foundation.

Central to this control effect are "step gaps" formed along the perimeter of each circle, which give the nanostructure the ability to modulate which waves of light pass through. It is within this geometry that the interaction of light upon the silver surface coating resulted in the excitation of plasmon waves, said Naughton. Examination of the SPPs by Mr. Ye using a near-field scanning optical microscope offered unique insights into the physics at work within the structure, Naughton said.

By adjusting the type of metal used to coat the structure or varying the circumferences of the microcavities, Naughton said the step-gap structure is capable of manipulating the optical properties of the device in the visible light range, giving the researchers newfound control in light filtering.

This kind of control, the team reports, could have applications in areas such as biomedical plasmonics or discrete optical filtering.


Story Source:

The above story is based on materials provided by Boston College. Note: Materials may be edited for content and length.


Journal Reference:

  1. Fan Ye, Michael J. Burns, Michael J. Naughton. Plasmonic Halos—Optical Surface Plasmon Drumhead Modes. Nano Letters, 2013; 130122111344000 DOI: 10.1021/nl303955x

Cite This Page:

Boston College. "Nanoscopic microcavities offer newfound control in light filtering: Unique nanostructure produces novel 'plasmonic halos'." ScienceDaily. ScienceDaily, 7 February 2013. <www.sciencedaily.com/releases/2013/02/130207150907.htm>.
Boston College. (2013, February 7). Nanoscopic microcavities offer newfound control in light filtering: Unique nanostructure produces novel 'plasmonic halos'. ScienceDaily. Retrieved July 23, 2014 from www.sciencedaily.com/releases/2013/02/130207150907.htm
Boston College. "Nanoscopic microcavities offer newfound control in light filtering: Unique nanostructure produces novel 'plasmonic halos'." ScienceDaily. www.sciencedaily.com/releases/2013/02/130207150907.htm (accessed July 23, 2014).

Share This




More Matter & Energy News

Wednesday, July 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Government Approves East Coast Oil Exploration

Government Approves East Coast Oil Exploration

AP (July 18, 2014) The Obama administration approved the use of sonic cannons to discover deposits under the ocean floor by shooting sound waves 100 times louder than a jet engine through waters shared by endangered whales and turtles. (July 18) Video provided by AP
Powered by NewsLook.com
Sunken German U-Boat Clearly Visible For First Time

Sunken German U-Boat Clearly Visible For First Time

Newsy (July 18, 2014) The wreckage of the German submarine U-166 has become clearly visible for the first time since it was discovered in 2001. Video provided by Newsy
Powered by NewsLook.com
Obama: U.S. Must Have "smartest Airports, Best Power Grid"

Obama: U.S. Must Have "smartest Airports, Best Power Grid"

Reuters - US Online Video (July 17, 2014) President Barak Obama stopped by at a lunch counter in Delaware before making remarks about boosting the nation's infrastructure. Mana Rabiee reports. Video provided by Reuters
Powered by NewsLook.com
Crude Oil Prices Bounce Back After Falling Below $100 a Barrel

Crude Oil Prices Bounce Back After Falling Below $100 a Barrel

TheStreet (July 16, 2014) Oil Futures are bouncing back after tumbling below $100 a barrel for the first time since May yesterday. Jeff Grossman is the president of BRG Brokerage and trades at the NYMEX. Grossman tells TheStreet the Middle East is always a concern for oil traders. Oil prices were pushed down in recent weeks on Libya increasing its production. Supply disruptions in Iraq fading also contributed to prices falling. News from China's economic front showing a growth for the second quarter also calmed fears on its slowdown. Jeff Grossman talks to TheStreet's Susannah Lee on this and more on the Energy Department's Energy Information Administration (EIA) report. Video provided by TheStreet
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins