Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Breaking barriers with nanoscale lasers

Abstract:
Thinnest semiconductor laser holds promise of better computers and Internet access

Breaking barriers with nanoscale lasers

Tempe, AZ | Posted on August 6th, 2009

We could soon see the potential of laser technology expand dramatically.

Ways to make lasers smaller are being discovered through collaborative efforts of researchers at Arizona State University and Technical University of Eindhoven in the Netherlands. The work opens up possibilities for using nanoscale lasers to significantly improve the performance of computers and speed up Internet access.

The teams' advances in breaking through previous limitations on how small lasers can be made are reported in a recent edition of the online science and engineering journal Optics Express.

Authors of the report include professor Martin Hill, who leads the Eindhoven team, and ASU team leader Cun-Zheng Ning, a professor in the School of Electrical, Computer and Energy Engineering in ASU's Ira A. Fulton Schools of Engineering.

Lasers once were the stuff largely of science fiction. Today they are everywhere in the world of electronics. They are essential components of CD and DVD players. They are used in the automatic check-out stations in supermarkets.

Small lasers are used in technology that enables communications across continents, and soon nanolasers will be used for communications between the parts inside your computer.

Engineers have been trying to make lasers smaller because it would enable the devices to be more effectively integrated with small electronics components. The more lasers that can be used with these components, the faster electronic devices could perform. This would do things such as speed up the workings of your computer and Internet access.

The size of lasers in any one dimension (for example, thickness) has been thought to be limited to one-half of the wavelength involved.

For instance, for lasers used in optical communications the required wavelength is about 1,500 nanometers, so a 750-nanometer laser was thought to be the smallest a laser could be made for optical communications.

In an optically denser medium such as a semiconductor, this limit is reduced by a factor of the index of refraction (expressed mathematically as ~3.0) of a semiconductor - in this case to about 250 nanometers.

The limit is sometimes called the diffraction limit, a property associated with any wave, such as a beam of light. Current theory says you can't make a laser smaller than this diffraction limit - or smaller than 250 nanometers for a semiconductor laser for communications devices.

The research teams at ASU and Eindhoven are showing there are ways around this supposed limit, Ning says.

One way is by the use of a combination of semiconductors and metals such as gold and silver.

"It turns out that the electrons excited in metals can help you confine a light in a laser to sizes smaller than that required by the diffraction limit," Ning explains. "Eventually, we were able to make a laser as thin as about one quarter of the wavelength or smaller, as opposed to one half."

Ning and Hill have achieved something like that by using a "metal-semiconductor-metal sandwich structure," in which the semiconductor is as thin as 80 nanometers and is sandwiched between 20-nanometer dielectric layers before putting metal layers on each side.

They have demonstrated that such a semiconductor/dielectric layer, thinner than the diffraction limit, and squeezed between metal layers, can actually emit laser light - a laser with the smallest thickness of any ever produced. The structure, however, has worked only in a low-temperature operating environment. The next step is to achieve the same laser light emission at room temperature.

Researchers worldwide are interested in integrating such metallic structures with semiconductors to produce smaller nanolasers because of the promise of applications for smaller lasers in a wide range of technologies.

"This is the first time that anyone has shown that this limit to the size of nanolasers can be broken," Ning says. "Beating this limit is significant. It opens up diverse possibilities for improving integrated communications devices, single molecule detection and medical imaging."

Nanoscale lasers can also be integrated with other biomedical diagnostic tools, making them work faster and more efficiently, he says.

These advances also represent a major step in nanophotonics - the study of the behavior of light on the nanometer scale and the ability to fabricate devices in nanoscale.

"Nanolasers can be used for many applications, but the most exciting possibilities are for communications on a central processing unit (CPU) of a computer chip," Ning says.

As computers get faster, the communication between different parts in a computer creates a processing bottleneck, he explains.

Since a signal can be transmitted between computer components much faster by a light wave emitted by a laser than by metal wires, optical communication (communication using light) is "the ultimate solution for improving on semiconductor chip communications," Ning says.

"But before this becomes a reality, lasers have to be made small enough to be integrated with small electronics components," he says. "This is why the Department of Defense and chip manufacturers such as Intel are working on optical solutions for on-chip communications."

Research in this field in the United States is being funded by the Defense Advanced Research Projects Agency (DARPA), the central research and development organization for the U.S. Department of Defense. The agency is supporting a collaborative team partnering researchers at ASU, the University of California at Berkeley and the University of Illinois, Urbana-Champaign.

ASU's collaboration with Hill's team at Eindhoven happened by coincidence, Ning says.

"We discovered we were working on the same problems and trying to achieve similar goals using similar ideas," he says. "So the partnership developed."

The Optics Express article can be found at www.opticsinfobase.org/DirectPDFAccess/0A7B4D8E-BDB9-137E-C5667E774627D931_182907.pdf?da=1&id=182907&seq=0&CFID=28345599&CFTOKEN=83759966

For more information on Ning's research group, visit the web site nanophotonics.asu.edu/

####

About Arizona State University
Arizona State University (also referred to as ASU, or Arizona State) is the largest public research university in the United States under a single administration, with total student enrollment of 67,082 as of fall 2008. ASU is spread across four campuses in the Phoenix Metropolitan Area.

From Wikipedia, the free encyclopedia

For more information, please click here

Contacts:
Joe Kullman

(480) 965-8122
Ira A. Fulton School of Engineering

Copyright © Arizona State University

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Tough foam from tiny sheets: Rice University lab uses atom-thick materials to make ultralight foam July 29th, 2014

Zenosense, Inc. July 29th, 2014

Optimum inertial design for self-propulsion: A new study investigates the effects of small but finite inertia on the propulsion of micro and nano-scale swimming machines July 29th, 2014

A new way to make microstructured surfaces: Method can produce strong, lightweight materials with specific surface properties July 29th, 2014

Govt.-Legislation/Regulation/Funding/Policy

Tough foam from tiny sheets: Rice University lab uses atom-thick materials to make ultralight foam July 29th, 2014

A new way to make microstructured surfaces: Method can produce strong, lightweight materials with specific surface properties July 29th, 2014

Seeing is bead-lieving: Rice University scientists create model 'bead-spring' chains with tunable properties July 28th, 2014

Stanford team achieves 'holy grail' of battery design: A stable lithium anode - Engineers use carbon nanospheres to protect lithium from the reactive and expansive problems that have restricted its use as an anode July 27th, 2014

Possible Futures

IBM Announces $3 Billion Research Initiative to Tackle Chip Grand Challenges for Cloud and Big Data Systems: Scientists and engineers to push limits of silicon technology to 7 nanometers and below and create post-silicon future July 10th, 2014

Virus structure inspires novel understanding of onion-like carbon nanoparticles April 10th, 2014

Local girl does good March 22nd, 2014

Surface Characteristics Influence Cellular Growth on Semiconductor Material March 12th, 2014

Chip Technology

A*STAR and industry form S$200M semiconductor R&D July 25th, 2014

A Crystal Wedding in the Nanocosmos July 23rd, 2014

Nanometrics Announces Upcoming Investor Events July 22nd, 2014

Penn Study: Understanding Graphene’s Electrical Properties on an Atomic Level July 22nd, 2014

Nanomedicine

Zenosense, Inc. July 29th, 2014

Optimum inertial design for self-propulsion: A new study investigates the effects of small but finite inertia on the propulsion of micro and nano-scale swimming machines July 29th, 2014

FEI adds Phase Plate Technology and Titan Halo TEM to its Structural Biology Product Portfolio: New solutions provide the high-quality imaging and contrast necessary to analyze the 3D structure of molecules and molecular complexes July 28th, 2014

New imaging agent provides better picture of the gut July 25th, 2014

Nanoelectronics

A*STAR and industry form S$200M semiconductor R&D July 25th, 2014

A Crystal Wedding in the Nanocosmos July 23rd, 2014

3-D nanostructure could benefit nanoelectronics, gas storage: Rice U. researchers predict functional advantages of 3-D boron nitride July 15th, 2014

IBM Announces $3 Billion Research Initiative to Tackle Chip Grand Challenges for Cloud and Big Data Systems: Scientists and engineers to push limits of silicon technology to 7 nanometers and below and create post-silicon future July 10th, 2014

Announcements

Tough foam from tiny sheets: Rice University lab uses atom-thick materials to make ultralight foam July 29th, 2014

Zenosense, Inc. July 29th, 2014

Optimum inertial design for self-propulsion: A new study investigates the effects of small but finite inertia on the propulsion of micro and nano-scale swimming machines July 29th, 2014

A new way to make microstructured surfaces: Method can produce strong, lightweight materials with specific surface properties July 29th, 2014

Nanobiotechnology

Harris & Harris Group Invests in Unique NYC Biotech Accelerator July 29th, 2014

Seeing is bead-lieving: Rice University scientists create model 'bead-spring' chains with tunable properties July 28th, 2014

FEI adds Phase Plate Technology and Titan Halo TEM to its Structural Biology Product Portfolio: New solutions provide the high-quality imaging and contrast necessary to analyze the 3D structure of molecules and molecular complexes July 28th, 2014

Scientists Test Nanoparticle "Alarm Clock" to Awaken Immune Systems Put to Sleep by Cancer July 25th, 2014

Photonics/Optics/Lasers

NUS scientists use low cost technique to improve properties and functions of nanomaterials: By 'drawing' micropatterns on nanomaterials using a focused laser beam, scientists could modify properties of nanomaterials for effective applications in photonic and optoelectric applicat July 22nd, 2014

Carbyne morphs when stretched: Rice University calculations show carbon-atom chain would go metal to semiconductor July 21st, 2014

Tiny laser sensor heightens bomb detection sensitivity July 19th, 2014

Future Electronics May Depend on Lasers, Not Quartz July 17th, 2014

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More














ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE