Featured Research

from universities, journals, and other organizations

Needle beam could eliminate signal loss in on-chip optics

Date:
September 7, 2012
Source:
Harvard School of Engineering and Applied Sciences
Summary:
An international team of researchers has demonstrated a new type of light beam that propagates without spreading outwards, remaining very narrow and controlled along an unprecedented distance. This "needle beam," as the team calls it, could greatly reduce signal loss for on-chip optical systems and may eventually assist the development of a more powerful class of microprocessors.

Federico Capasso (left), Patrice Genevet (right), and an international team of colleagues have demonstrated a new type of tightly controlled light wave that could eliminate signal loss in on-chip optical devices.
Credit: Photo by Eliza Grinnell, SEAS Communications

An international, Harvard-led team of researchers has demonstrated a new type of light beam that propagates without spreading outwards, remaining very narrow and controlled along an unprecedented distance. This "needle beam," as the team calls it, could greatly reduce signal loss for on-chip optical systems and may eventually assist the development of a more powerful class of microprocessors.

Related Articles


Based at the Harvard School of Engineering and Applied Sciences (SEAS) and the Laboratoire Interdisciplinaire Carnot de Bourgogne, CNRS, in France, the applied physicists both characterized and created this needle beam, which travels efficiently at the interface of gold and air. Their findings were published online Aug. 31 in the journal Physical Review Letters.

The needle beam arises from a special class of quasiparticles called surface plasmons, which travel in tight confinement with a metal surface. The metallic stripes that carry these surface plasmons have the potential to replace standard copper electrical interconnects in microprocessors, enabling ultrafast on-chip communications.

One of the fundamental problems that has so far hindered the development of such optical interconnects is the fact that all waves naturally spread laterally during propagation, a phenomenon known as diffraction. This reduces the portion of the signal that can actually be detected.

"We have made a major step toward solving this problem by discovering and experimentally confirming the existence of a previously overlooked solution of Maxwell's equations that govern all light phenomena," says principal investigator Federico Capasso, Robert L. Wallace Professor of Applied Physics and Vinton Hayes Senior Research Fellow in Electrical Engineering at SEAS. "The solution is a highly localized surface plasmon wave that propagates for a long distance, approximately 80 microns in our experiments, in a straight line without any diffraction."

The so-called needle beam, the technical term for which is a cosine-Gauss plasmon beam, propagates in tight confinement with a nanostructured metal surface. Lead author Jiao Lin, a visiting postdoctoral fellow at SEAS from the Singapore Institute of Manufacturing and Technology, and coauthor Patrice Genevet, a research associate in Capasso's group, found an ingenious way to demonstrate the theorized phenomenon. They sculpted two sets of grooves into a gold film that was plated onto the surface of a glass sheet. These tiny grooves intersect at an angle to form a metallic grating. When illuminated by a laser, the device launches two tilted, plane surface waves which interfere constructively to create the non-diffracting beam.

"Our French colleagues did a beautiful experiment, using an ultrahigh-resolution microscope to image the needle-shaped beam propagating for a long distance across the gold surface," says Genevet.

Capasso's team hopes the finding will assist the development of more energy-efficient and powerful microprocessors.


Story Source:

The above story is based on materials provided by Harvard School of Engineering and Applied Sciences. Note: Materials may be edited for content and length.


Journal Reference:

  1. Jiao Lin, Jean Dellinger, Patrice Genevet, Benoit Cluzel, Frederique de Fornel, Federico Capasso. Cosine-Gauss Plasmon Beam: A Localized Long-Range Nondiffracting Surface Wave. Physical Review Letters, 2012; 109 (9) DOI: 10.1103/PhysRevLett.109.093904

Cite This Page:

Harvard School of Engineering and Applied Sciences. "Needle beam could eliminate signal loss in on-chip optics." ScienceDaily. ScienceDaily, 7 September 2012. <www.sciencedaily.com/releases/2012/09/120907072322.htm>.
Harvard School of Engineering and Applied Sciences. (2012, September 7). Needle beam could eliminate signal loss in on-chip optics. ScienceDaily. Retrieved April 21, 2015 from www.sciencedaily.com/releases/2012/09/120907072322.htm
Harvard School of Engineering and Applied Sciences. "Needle beam could eliminate signal loss in on-chip optics." ScienceDaily. www.sciencedaily.com/releases/2012/09/120907072322.htm (accessed April 21, 2015).

Share This


More From ScienceDaily



More Matter & Energy News

Tuesday, April 21, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Humanoid Robot Can Recognise and Interact With People

Humanoid Robot Can Recognise and Interact With People

Reuters - Innovations Video Online (Apr. 20, 2015) An ultra-realistic humanoid robot called &apos;Han&apos; recognises and interprets people&apos;s facial expressions and can even hold simple conversations. Developers Hanson Robotics hope androids like Han could have uses in hospitality and health care industries where face-to-face communication is vital. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
Drones and Health Apps at Santiago's "Robotics Day"

Drones and Health Apps at Santiago's "Robotics Day"

AFP (Apr. 20, 2015) Latin American robotics experts gather in Santiago, Chile for "Robotics Day". Video provided by AFP
Powered by NewsLook.com
Japan Humanoid Robot Receives Customers at Department Store

Japan Humanoid Robot Receives Customers at Department Store

AFP (Apr. 20, 2015) She can smile, she can sing and she can give you guidance at one of the most upscale department stores in Tokyo...a female-looking humanoid makes her debut as a receptionist Video provided by AFP
Powered by NewsLook.com
Pee-Power Toilet to Light Up Disaster Zones

Pee-Power Toilet to Light Up Disaster Zones

Reuters - Innovations Video Online (Apr. 20, 2015) Students and staff are being asked to use a prototype urinal to &apos;donate&apos; urine to fuel microbial fuel cell (MFC) stacks that generate electricity to power lighting. The developers hope the pee-power technology will light toilet cubicles in refugee camps, where women are often at risk of assault in poorly lit sanitation areas. Matthew Stock reports. Video provided by Reuters
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