Featured Research

from universities, journals, and other organizations

Optics: Nanotechnology's benefits brought into focus

Date:
August 31, 2013
Source:
The Agency for Science, Technology and Research (A*STAR)
Summary:
Conventional lenses, made of shaped glass, are limited in how precisely they can redirect beams of incoming light and make them meet at a point. Now, scientists have proposed a novel approach to 'superlens' systems that can surpass this classical limit of focusing light.

Conventional lenses, made of shaped glass, are limited in how precisely they can redirect beams of incoming light and make them meet at a point. Now, a team led by Zhengtong Liu at the A*STAR Institute of High Performance Computing, Singapore, has proposed a novel approach to 'superlens' systems that can surpass this classical limit of focusing light.

The team used numerical modeling to develop the design. Concentrating radiation into a smaller volume in this way enhances the interaction between light and matter, and thus the concept could prove useful in highly sensitive sensors of the future.

Light is a type of wave. Unlike the rise and fall in sea water at a beach, however, a light wave consists of oscillating electric and magnetic fields. The wavelength -- the distance a wave travels in one oscillation cycle -- imposes a limit on the minimum size to which light can be focused. However, this limit does not apply over small distances that are comparable to the wavelength, which is known as the near-field regime.

The researchers designed a silver nanostructure embedded in glass. Their device combined two separate elements. One component was a nanoantenna -- similar to the radio-frequency antennas used to detect television-carrying signals, but reduced in size to match the wavelength of optical radiation. The other component was a superlens made of a thin slab of silver. The purpose of the superlens was to move the light detected by the nanoantenna into an imaging plane. "Using nanoantennas to concentrate light is not a new idea," says Liu. "But by adding a superlens to translate the concentrated spot of light, we can overcome limitations imposed by the optical properties of the material."

Liu and co-workers mathematically modeled the optical response of this device to an incoming beam of red light. They then altered the dimensions of the structure to maximize the enhancement in electric field. In this way, they were able to show that a 20-nanometer-thick superlens, separated by 34 nanometers from an antenna made of two silver ellipses, could increase the electric field of light by a factor of 250.

Confining light into these super intense 'hot-spots' could prove a boon for optical detection systems. "Our concept is targeted at biomedical and chemical sensing applications," explains Liu. "The next step is to seek collaboration opportunities to actually make the sensor and test it in the field."


Story Source:

The above story is based on materials provided by The Agency for Science, Technology and Research (A*STAR). Note: Materials may be edited for content and length.


Journal Reference:

  1. Liu, Z., Li, E., Shalaev, V. M. & Kildishev, A. V. Near field enhancement in silver nanoantenna-superlens systems. Applied Physics Letters, 101, 021109 (2012)

Cite This Page:

The Agency for Science, Technology and Research (A*STAR). "Optics: Nanotechnology's benefits brought into focus." ScienceDaily. ScienceDaily, 31 August 2013. <www.sciencedaily.com/releases/2013/08/130831110653.htm>.
The Agency for Science, Technology and Research (A*STAR). (2013, August 31). Optics: Nanotechnology's benefits brought into focus. ScienceDaily. Retrieved July 28, 2014 from www.sciencedaily.com/releases/2013/08/130831110653.htm
The Agency for Science, Technology and Research (A*STAR). "Optics: Nanotechnology's benefits brought into focus." ScienceDaily. www.sciencedaily.com/releases/2013/08/130831110653.htm (accessed July 28, 2014).

Share This




More Matter & Energy News

Monday, July 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Europe's Highest Train Turns 80 in French Pyrenees

Europe's Highest Train Turns 80 in French Pyrenees

AFP (July 25, 2014) Europe's highest train, the little train of Artouste in the French Pyrenees, celebrates its 80th birthday. Duration: 01:05 Video provided by AFP
Powered by NewsLook.com
TSA Administrator on Politics and Flight Bans

TSA Administrator on Politics and Flight Bans

AP (July 24, 2014) TSA administrator, John Pistole's took part in the Aspen Security Forum 2014, where he answered questions on lifting of the ban on flights into Israel's Tel Aviv airport and whether politics played a role in lifting the ban. (July 24) Video provided by AP
Powered by NewsLook.com
Creative Makeovers for Ugly Cellphone Towers

Creative Makeovers for Ugly Cellphone Towers

AP (July 24, 2014) Mobile phone companies and communities across the country are going to new lengths to disguise those unsightly cellphone towers. From a church bell tower to a flagpole, even a pencil, some towers are trying to make a point. (July 24) Video provided by AP
Powered by NewsLook.com
Algonquin Power Goes Activist on Its Target Gas Natural

Algonquin Power Goes Activist on Its Target Gas Natural

TheStreet (July 23, 2014) When The Deal's Amanda Levin exclusively reported that Gas Natural had been talking to potential suitors, the Ohio company responded with a flat denial, claiming its board had not talked to anyone about a possible sale. Lo and behold, Canadian utility Algonquin Power and Utilities not only had approached the company, but it did it three times. Its last offer was for $13 per share as Gas Natural's was trading at a 60-day moving average of about $12.50 per share. Now Algonquin, which has a 4.9% stake in Gas Natural, has taken its case to shareholders, calling on them to back its proposals or, possibly, a change in the target's board. 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