Nanotechnology Now

Our NanoNews Digest Sponsors



Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Breaking the final barrier: room-temperature electrically powered nanolasers

The illustration on the left shows the variations of light intensity within a nanolaser. The figure on the right shows schematically a nanolaser with a metallic cavity, where the center red region confines electrons and the grey enclosure is a silver cavity. The blue layer on top is a substrate where the laser structure is grown. The orange-yellow color on top indicates the light emission. Research led by Arizona state University engineering professor Cun-Zheng Ning has produced nanolasers that can operate under a battery power at room temperatures  instead of only in refrigerated conditions  which opens the door to use of the lasers in many practical applications in modern electronics.
The illustration on the left shows the variations of light intensity within a nanolaser. The figure on the right shows schematically a nanolaser with a metallic cavity, where the center red region confines electrons and the grey enclosure is a silver cavity. The blue layer on top is a substrate where the laser structure is grown. The orange-yellow color on top indicates the light emission. Research led by Arizona state University engineering professor Cun-Zheng Ning has produced nanolasers that can operate under a battery power at room temperatures instead of only in refrigerated conditions which opens the door to use of the lasers in many practical applications in modern electronics.

Abstract:
A breakthrough in nanolaser technology has been made by Arizona State University researchers.

Electrically powered nano-scale lasers have been able to operate effectively only in cold temperatures. Researchers in the field have been striving to enable them to perform reliably at room temperature, a step that would pave the way for their use in a variety of practical applications.

Breaking the final barrier: room-temperature electrically powered nanolasers

Tempe, AZ | Posted on March 12th, 2013

Details of how ASU researchers made that leap are published in a recent issue of the research journal Optics Express (Vol. 21, No. 4, 4728 2013).

The research team is led by Cun-Zheng Ning, an electrical engineering professor in the School of Electrical, Computer and Energy Engineering, one of ASU's Ira A. Fulton Schools of Engineering.

He has been among engineers and scientists across the world attempting to fabricate a workable nanolaser with a volume smaller than its wavelength cubed - an intermediate step toward further miniaturization of lasers.

Miniaturizing lasers is crucial to making electronics smaller and better, and enabling them to operate faster. Packing more lasers into smaller spaces is necessary for downsized devices to maintain high performance. Being able to integrate more lasers onto a small microchip would make the next generations of computers faster and smaller. The wavelength scale is the next milestone to be achieved in the overall effort to enable more miniaturization.

Refining the shrinking technique

Ning explains that extremely small and thin lasers have been developed, but they needed to be optically driven by a larger laser. In addition, current electrically driven nanolasers can operate only at low temperatures or and emit light only in short bursts or pulses.

To enable them to be useful in practical applications - particularly for improvements of electronic and photonic technologies - it's necessary that the laser operates at room temperature without a refrigeration system, that it be powered by a simple battery instead of by another laser, and that it is able to emit light continuously.

"That has been the ultimate goal in the nanolaser research community," Ning says.

Ning's team started looking for solutions almost seven years ago, before he joined ASU, with his then- postdoctoral assistant, Alex Maslov, who is currently a scientist with Canon USA Inc.

While working for the National Aeronautics and Space Administration's Ames Research Center, they proposed a semiconductor wire coated with a silver shell. They showed that such a core-shell structure was able to shrink the nanolaser to an incredibly small scale.

About four years ago, working with Martin Hill, a former professor at Eindhoven University of Technology in the Netherlands, the team developed the thinnest nanolaser capable of operating at low temperatures. Two years ago, with the aid of Ning's student, Kang Ding, they were able to raise the operating temperature to 260 Kelvin (8.33 degrees Fahrenheit).

Significant impacts

More recently the team demonstrated a device that could operate at room temperature (read the article in the journal Physical Review B), but the overheating led to imperfect device operation and a conclusive demonstration of lasing remained elusive.

The most recent results, however, demonstrated an eight-fold improvement over previous results from a year ago, finally providing an unambiguous demonstration of continuous electrically driven operation of a laser at room temperature, Ning says.

To explain the significance of such an advance, Ning says, "Imagine if computers had to be cooled down to minus 200 Celsius (minus 350 degrees Fahrenheit) for our current information technology to work. If that were the case, we would not have the widespread usage of computers and social media."

With nanolasers that can operate at room temperature and be powered by a simple battery, they can be used to make computers operate faster, significantly broaden Internet bandwidth, and provide light sources for many computer-chip-based sensing and detection technologies.

Show-stopping advance

But the benefits of achieving continuous room temperature operation go beyond the practical aspects, Ning says.

"In terms of fundamental science, it shows for the first time that metal heating loss is not an insurmountable barrier for room-temperature operation of a metallic cavity nanolaser under electrical injection. For a long time, many doubted if such operation is even possible at all," he says.

"Unlike nanolasers driven by another laser, where the driving laser can be chosen so that the heat generation is minimized, electrical injection by a battery produces more heat. In addition, typical metals can be heated quickly by the operation of the nanolasers. Thus, such elevated heat generation has been perceived as a show-stopper for such nanolasers," Ning says.

He adds: "More importantly, similar metal semiconductor structures used for nanolasers are also currently being explored for many other applications, such as being a building block for the formation of artificial materials that have remarkable properties. This demonstration is thus also important to the researchers working in those areas of materials science and engineering."

Crediting collaborators

The breakthrough by Ning's team required skillful nanofabrication and measurements. Credit for that contribution to the research goes to several of his students, primarily Kang Ding, Leijun Yin, and Zhicheng Liu. Yin is pursuing his doctorate in physics. Ding and Liu are pursuing doctoral degrees in electrical engineering.

"It is extremely challenging to get everything correct at the nanometer scale. At such a small scale, any fabrication error becomes relatively large, and there are many fabrication steps, each of which is rather complex," he says.

The team also benefited greatly from long-term collaboration with Martin Hill and his colleagues who provided technical support, especially Meint Smit, a professor of electrical engineering at Eindhoven University of Technology, who allowed the use of the university's advanced fabrication facility during the final phase of the research.

The research has been supported by the Defense Advanced Project Agency (an agency of the U.S. Department of Defense), and by the Air Force Office of Scientific Research.

Ning points to several managers at the agencies - including Henryk Temkin, Michael Haney, Scott Rodgers, Michael Gerhold, and Gernot Pomrenke - who were willing to support the project despite skepticism.

Remaining challenges

"Many experts questioned the feasibility of such a project and doubted if we would ever be able to make such a small laser, let alone one that worked at room temperature," he says. "But we were convinced of the novelty and significance of such a project. With the support and trust of these agencies, we were eventually able to achieve or exceed many of our initial goals. "

Ning says many challenges remain in efforts to integrate nanolasers into a photonic system on-chip platform, as well as to prolong the lifetime of laser operation, and to further develop the capabilities of such devices. In addition, the physical mechanisms involved in the interaction of photons with metallic structures on small scale are not yet fully understood, so there is still much research to be done in this area.

"But thanks to the realization of room-temperature operation of nanolasers, all these goals can start to be more effectively explored," Ning says.

####

For more information, please click here

Contacts:
Joe Kullman

480-965-8122

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 Links

Read the full article:

Related News Press

News and information

Switching to spintronics: Berkeley Lab reports on electric field switching of ferromagnetism at room temp December 17th, 2014

ORNL microscopy pencils patterns in polymers at the nanoscale December 17th, 2014

Unraveling the light of fireflies December 17th, 2014

First Home-Made Edible Herbal Nanodrug Presented to Pharmacies across Iran December 17th, 2014

Discoveries

Switching to spintronics: Berkeley Lab reports on electric field switching of ferromagnetism at room temp December 17th, 2014

ORNL microscopy pencils patterns in polymers at the nanoscale December 17th, 2014

Unraveling the light of fireflies December 17th, 2014

Fraud-proof credit card possible because of quantum physics December 16th, 2014

Materials/Metamaterials

ORNL microscopy pencils patterns in polymers at the nanoscale December 17th, 2014

Pb islands in a sea of graphene magnetise the material of the future December 16th, 2014

Graphene Applied in Production of Recyclable Electrodes December 13th, 2014

A golden thread through the labyrinth of nanomaterials December 12th, 2014

Announcements

Switching to spintronics: Berkeley Lab reports on electric field switching of ferromagnetism at room temp December 17th, 2014

ORNL microscopy pencils patterns in polymers at the nanoscale December 17th, 2014

Unraveling the light of fireflies December 17th, 2014

First Home-Made Edible Herbal Nanodrug Presented to Pharmacies across Iran December 17th, 2014

Tools

Switching to spintronics: Berkeley Lab reports on electric field switching of ferromagnetism at room temp December 17th, 2014

ORNL microscopy pencils patterns in polymers at the nanoscale December 17th, 2014

Unraveling the light of fireflies December 17th, 2014

Bruker Introduces BioScope Resolve High-Resolution BioAFM System: Featuring PeakForce Tapping for Quantitative Bio-Mechanical Property Mapping December 16th, 2014

Photonics/Optics/Lasers

Nanoshaping method points to future manufacturing technology December 11th, 2014

Stacking two-dimensional materials may lower cost of semiconductor devices December 11th, 2014

Defects are perfect in laser-induced graphene: Rice University lab discovers simple way to make material for energy storage, electronics December 10th, 2014

New technique allows low-cost creation of 3-D nanostructures December 8th, 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