Featured Research

from universities, journals, and other organizations

Optical nanoantennas enable efficient multipurpose particle manipulation

Date:
January 19, 2012
Source:
University of Illinois College of Engineering
Summary:
Researchers have shown that by tuning the properties of laser light illuminating arrays of metal nanoantennas, these nano-scale structures allow for dexterous optical tweezing as well as size-sorting of particles.

Concept art depicting various potential BNA trapping states.
Credit: Image courtesy of University of Illinois College of Engineering

University of Illinois researchers have shown that by tuning the properties of laser light illuminating arrays of metal nanoantennas, these nano-scale structures allow for dexterous optical tweezing as well as size-sorting of particles.

Related Articles


"Nanoantennas are extremely popular right now because they are really good at concentrating optical fields in small areas," explained Kimani Toussaint, Jr., an assistant professor of mechanical science and engineering at the University of Illinois at Urbana-Champaign. "In this work, we demonstrate for the first time the use of arrays of gold Bowtie Nanoantenna Arrays (BNAs) for multipurpose optical trapping and manipulation of submicrometer- to micrometer-sized objects. We think that this could be a fruitful area to pursue, particularly because of the growing interest in lab-on-a-chip devices."

According to the researchers, the excellent field enhancement and confinement properties of BNAs enable highly efficient, optical tweezers which permit high-speed manipulation of submicrometer to micrometer-sized objects in aqueous environments using remarkably low-input power densities. These characteristics could be useful for optofluidic applications (e.g., lab-on-a-chip devices), manipulating biological matter with reduced specimen photo damage, formation of optical matter, and basic physics studies of colloidal dynamics.

"In contrast to other plasmonic tweezers, we find that BNAs permit particle trapping, manipulation and sorting utilizing only the optical parameter space, namely, low input power densities, wavelength and polarization," said Brian Roxworthy, a graduate student in Toussaint's research group and first author on the paper, "Application of Plasmonic Bowtie Nanoantenna Arrays for Optical Trapping, Stacking, and Sorting," which appears in the journal Nano Letters.

Using empirically obtained "optical trapping phase diagrams" to achieve the desired trapping response, the researchers demonstrated several types of particle manipulation, including single-beam optical tweezing of single particles over the entire nanoantenna area, single-beam optical tweezing of 2D hexagonal packed particles over the entire nanoantenna area, and optical sorting of particles by size; stacking of submicron to micron-sized particles in 3D.

According to Toussaint, this is the first demonstration of a range of particle manipulation behavior for a given nanoantenna array.

"We actually excite our nanoantennas off resonance, which to our knowledge is a first, and at the right input optical power, we take advantage of thermal effects combined with optical forces to enable tweezing of tens of particles at a time," Toussaint explained. "We show that very low power densities are required to achieve the aforementioned behavior. For example, we were able to carry out experiments using a standard laser pointer."

In addition to Toussaint, the lead investigator for the project, co-investigators include Gang Logan Liu, an assistant professor of electrical and computer engineering at Illinois, and former Illinois faculty member Nicholas Fang, who is now at the Massachusetts Institute of Technology.


Story Source:

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


Journal Reference:

  1. Brian J. Roxworthy, Kaspar D. Ko, Anil Kumar, Kin Hung Fung, Edmond K. C. Chow, Gang Logan Liu, Nicholas X. Fang, Kimani C. Toussaint. Application of Plasmonic Bowtie Nanoantenna Arrays for Optical Trapping, Stacking, and Sorting. Nano Letters, 2012; 120109094850008 DOI: 10.1021/nl203811q

Cite This Page:

University of Illinois College of Engineering. "Optical nanoantennas enable efficient multipurpose particle manipulation." ScienceDaily. ScienceDaily, 19 January 2012. <www.sciencedaily.com/releases/2012/01/120112134330.htm>.
University of Illinois College of Engineering. (2012, January 19). Optical nanoantennas enable efficient multipurpose particle manipulation. ScienceDaily. Retrieved March 5, 2015 from www.sciencedaily.com/releases/2012/01/120112134330.htm
University of Illinois College of Engineering. "Optical nanoantennas enable efficient multipurpose particle manipulation." ScienceDaily. www.sciencedaily.com/releases/2012/01/120112134330.htm (accessed March 5, 2015).

Share This


More From ScienceDaily



More Matter & Energy News

Thursday, March 5, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Gas Production Cut on Earthquake Fears

Gas Production Cut on Earthquake Fears

Reuters - Business Video Online (Mar. 5, 2015) — The Dutch government has cut production at Europe&apos;s largest gas field in Groningen amid concerns over earthquakes which are damaging local churches. As Amy Pollock reports the decision - largely politically-motivated - could have big economic conseqeunces. Video provided by Reuters
Powered by NewsLook.com
Star Wars-Inspired Prototype Creates Holographic Display

Star Wars-Inspired Prototype Creates Holographic Display

Reuters - Innovations Video Online (Mar. 5, 2015) — A prototype holographic display named Leia - after the Star Wars princess who appeared in holographic form asking Obi-Wan Kenobu for help - is demonstrated at the Mobile World Congress in Barcelona. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
IKEA and Samsung Launch Embedded Wireless Charging Range

IKEA and Samsung Launch Embedded Wireless Charging Range

Reuters - Innovations Video Online (Mar. 5, 2015) — Samsung and IKEA hope their new embedded wireless charging products, launched at Barcelona&apos;s Mobile World Congress, will tempt consumers eager for plugless power. Jim Drury reports. Video provided by Reuters
Powered by NewsLook.com
Samsung Unveils $30,000 'Dream Doghouse'

Samsung Unveils $30,000 'Dream Doghouse'

Buzz60 (Mar. 5, 2015) — On display at the Crufts dog show in England, the &apos;dog kennel of the future&apos; comes with features like a doggie treadmill and Samsung tablet. Mike Janela (@mikejanela) has more. Video provided by Buzz60
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:

Strange & Offbeat Stories

 

Space & Time

Matter & Energy

Computers & Math

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