Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


DHgate

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

Artificial leaf harnesses sunlight for efficient fuel production August 30th, 2015

Researchers use DNA 'clews' to shuttle CRISPR-Cas9 gene-editing tool into cells August 30th, 2015

Draw out of the predicted interatomic force August 30th, 2015

Iranian Scientists Use Artemisia Annua Plant to Produce Breast Cancer Drugs August 29th, 2015

Govt.-Legislation/Regulation/Funding/Policy

Artificial leaf harnesses sunlight for efficient fuel production August 30th, 2015

Researchers use DNA 'clews' to shuttle CRISPR-Cas9 gene-editing tool into cells August 30th, 2015

Draw out of the predicted interatomic force August 30th, 2015

These microscopic fish are 3-D-printed to do more than swim: Researchers demonstrate a novel method to build microscopic robots with complex shapes and functionalities August 26th, 2015

Possible Futures

Sediment dwelling creatures at risk from nanoparticles in common household products August 13th, 2015

Harris & Harris Group Reports Financial Statements as of June 30, 2015, and Announces a Stock Repurchase Program August 10th, 2015

Molecular trick alters rules of attraction for non-magnetic metals August 5th, 2015

Global Carbon Nanotubes Industry 2015: Acute Market Reports August 4th, 2015

Chip Technology

Nanometrics to Participate in the Citi 2015 Global Technology Conference August 26th, 2015

Kwansei Gakuin University in Hyogo, Japan, uses Raman microscopy to study crystallographic defects in silicon carbide wafers August 25th, 2015

A little light interaction leaves quantum physicists beaming August 25th, 2015

'Magic' sphere for information transfer: Professor at the Lomonosov Moscow State University made the «magic» sphere for information transfer August 24th, 2015

Nanomedicine

Researchers use DNA 'clews' to shuttle CRISPR-Cas9 gene-editing tool into cells August 30th, 2015

Iranian Scientists Use Artemisia Annua Plant to Produce Breast Cancer Drugs August 29th, 2015

Small but heading for the big time: Nanobiotix half year results for the six months ended 30 June 2015, in line with expectations: Major clinical achievements and corporate developments August 28th, 2015

A new technique to make drugs more soluble August 28th, 2015

Nanoelectronics

Nanotechnology that will impact the Security & Defense sectors to be discussed at NanoSD2015 conference August 25th, 2015

'Quantum dot' technology may help light the future August 19th, 2015

Surprising discoveries about 2-D molybdenum disulfide: Berkeley Lab researchers use award-winning campanile probe on promising semiconductor August 15th, 2015

Better together: Graphene-nanotube hybrid switches August 3rd, 2015

Announcements

Artificial leaf harnesses sunlight for efficient fuel production August 30th, 2015

Researchers use DNA 'clews' to shuttle CRISPR-Cas9 gene-editing tool into cells August 30th, 2015

Draw out of the predicted interatomic force August 30th, 2015

Iranian Scientists Use Artemisia Annua Plant to Produce Breast Cancer Drugs August 29th, 2015

Nanobiotechnology

Researchers use DNA 'clews' to shuttle CRISPR-Cas9 gene-editing tool into cells August 30th, 2015

Small but heading for the big time: Nanobiotix half year results for the six months ended 30 June 2015, in line with expectations: Major clinical achievements and corporate developments August 28th, 2015

Nanotechnology that will impact the Security & Defense sectors to be discussed at NanoSD2015 conference August 25th, 2015

Louisiana Tech University researchers discover synthesis of a new nanomaterial: Interdisciplinary team creates biocomposite for first time using physiological conditions August 24th, 2015

Photonics/Optics/Lasers

Glitter from silver lights up Alzheimer's dark secrets August 25th, 2015

Quantum diffraction at a breath of nothing: Physicists build stable diffraction structure in atomically thin graphene August 25th, 2015

Nanotechnology that will impact the Security & Defense sectors to be discussed at NanoSD2015 conference August 25th, 2015

A little light interaction leaves quantum physicists beaming August 25th, 2015

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







Car Brands
Buy website traffic