Nanotechnology Now







Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Engineers take plasmon lasers out of deep freeze

Abstract:
Researchers at the University of California, Berkeley, have developed a new technique that allows plasmon lasers to operate at room temperature, overcoming a major barrier to practical utilization of the technology.

Engineers take plasmon lasers out of deep freeze

Berkeley, CA | Posted on December 19th, 2010

The achievement, described Dec. 19 in an advanced online publication of the journal Nature Materials (*), is a "major step towards applications" for plasmon lasers, said the research team's principal investigator, Xiang Zhang, UC Berkeley professor of mechanical engineering and faculty scientist at Lawrence Berkeley National Laboratory.

"Plasmon lasers can make possible single-molecule biodetectors, photonic circuits and high-speed optical communication systems, but for that to become reality, we needed to find a way to operate them at room temperature," said Zhang, who also directs at UC Berkeley the Center for Scalable and Integrated Nanomanufacturing, established through the National Science Foundation's (NSF) Nano-scale Science and Engineering Centers program.

In recent years, scientists have turned to plasmon lasers, which work by coupling electromagnetic waves with the electrons that oscillate at the surface of metals to squeeze light into nanoscale spaces far past its natural diffraction limit of half a wavelength. Last year, Zhang's team reported a plasmon laser that generated visible light in a space only 5 nanometers wide, or about the size of a single protein molecule.

But efforts to exploit such advancements for commercial devices had hit a wall of ice.

"To operate properly, plasmon lasers need to be sealed in a vacuum chamber cooled to cryogenic temperatures as low as 10 kelvins, or minus 441 degrees Fahrenheit, so they have not been usable for practical applications," said Renmin Ma, a post-doctoral researcher in Zhang's lab and co-lead author of the Nature Materials paper.

In previous designs, most of the light produced by the laser leaked out, which required researchers to increase amplification of the remaining light energy to sustain the laser operation. To accomplish this amplification, or gain increase, researchers put the materials into a deep freeze.

To plug the light leak, the scientists took inspiration from a whispering gallery, typically an enclosed oval-shaped room located beneath a dome in which sound waves from one side are reflected back to the other. This reflection allows people on opposite sides of the gallery to talk to each other as if they were standing side by side. (Some notable examples of whispering galleries include the U.S. Capitol's Statuary Hall, New York's Grand Central Terminal, and the rotunda at San Francisco's city hall.)

Instead of bouncing back sound waves, the researchers used a total internal reflection technique to bounce surface plasmons back inside a nano-square device. The configuration was made out of a cadmium sulfide square measuring 45 nanometers thick and 1 micrometer long placed on top of a silver surface and separated by a 5 nanometer gap of magnesium fluoride.

The scientists were able to enhance by 18-fold the emission rate of light, and confine the light to a space of about 20 nanometers, or one-twentieth the size of its wavelength. By controlling the loss of radiation, it was no longer necessary to encase the device in a vacuum cooled with liquid helium. The laser functioned at room temperature.

"The greatly enhanced light matter interaction rates means that very weak signals might be observable," said Ma. "Lasers with a mode size of a single protein are a key milestone toward applications in ultra-compact light source in communications and biomedical diagnostics. The present square plasmon cavities not only can serve as compact light sources, but also can be the key components of other functional building-blocks in integrated circuits, such as add-drop filters, direction couplers and modulators."

Rupert Oulton, a former post-doctoral researcher in Zhang's lab and now a lecturer at Imperial College London, is the other co-lead author of the paper. Other co-authors are Volker Sorger, a UC Berkeley Ph.D. student in mechanical engineering, and Guy Bartal, a former research scientist in Zhang's lab.

The U.S. Air Force Office of Scientific Research and the NSF helped support this work.

(*) www.nature.com/nmat/journal/vaop/ncurrent/full/nmat2919.html

####

For more information, please click here

Contacts:
Media contact:
Sarah Yang
(510) 643-7741


Source:
Xiang Zhang
(510) 225-8559

Copyright © University of California, Berkeley

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

Why Is Google Making Synthetic Arms? February 1st, 2015

Nanomaterials Used to Reduce Heat Generated by LED Panels February 1st, 2015

Leader Describes Iran's Independence as Root Cause of Bullying Powers' Enmity February 1st, 2015

Performance Drop in Solar Cells Prevented by Nanotechnology February 1st, 2015

Govt.-Legislation/Regulation/Funding/Policy

Leader Describes Iran's Independence as Root Cause of Bullying Powers' Enmity February 1st, 2015

Evidence mounts for quantum criticality theory: Findings bolster theory that quantum fluctuations drive strange electronic phenomena January 30th, 2015

Nanoscale Mirrored Cavities Amplify, Connect Quantum Memories: Advance could lead to quantum computing and the secure transfer of information over long-distance fiber optic networks January 28th, 2015

Detecting chemical weapons with a color-changing film January 28th, 2015

Possible Futures

Leader Describes Iran's Independence as Root Cause of Bullying Powers' Enmity February 1st, 2015

GS7 Graphene Sensor maybe Solution in Fight Against Cancer January 25th, 2015

Nanotechnology in Energy Applications Market Research Report 2014-2018: Radiant Insights, Inc January 15th, 2015

'Mind the gap' between atomically thin materials December 23rd, 2014

Academic/Education

Rice's Naomi Halas to direct Smalley Institute: Optics pioneer will lead Rice's multidisciplinary science institute January 15th, 2015

SUNY Board Appoints Dr. Alain Kaloyeros as Founding President of SUNY Polytechnic Institute January 13th, 2015

CNSE's Smart System Technology & Commercialization Center Successfully Recertifies as ISO 9001:2008 January 12th, 2015

SUNY Poly Now Accepting Applications to the Colleges of Nanoscale Science and Engineering for Fall 2015: Full Scholarships Available to Incoming CNSE Students January 7th, 2015

Nanomedicine

Why Is Google Making Synthetic Arms? February 1st, 2015

DNA nanoswitches reveal how life's molecules connect: An accessible new way to study molecular interactions could lower cost and time associated with discovering new drugs January 30th, 2015

Made-in-Singapore rapid test kit detects dengue antibodies from saliva: IBN's MedTech innovation simplifies diagnosis of infectious diseases January 29th, 2015

Iranian Researchers Planning to Produce Edible Insulin January 28th, 2015

Nanoelectronics

Electronic circuits with reconfigurable pathways closer to reality January 26th, 2015

Rice-sized laser, powered one electron at a time, bodes well for quantum computing January 15th, 2015

Rapid journey through a crystal lattice: Researchers measure how fast electrons move through single atomic layers January 14th, 2015

A new step towards using graphene in electronic applications January 14th, 2015

Announcements

Why Is Google Making Synthetic Arms? February 1st, 2015

Nanomaterials Used to Reduce Heat Generated by LED Panels February 1st, 2015

Leader Describes Iran's Independence as Root Cause of Bullying Powers' Enmity February 1st, 2015

Performance Drop in Solar Cells Prevented by Nanotechnology February 1st, 2015

Nanobiotechnology

DNA nanoswitches reveal how life's molecules connect: An accessible new way to study molecular interactions could lower cost and time associated with discovering new drugs January 30th, 2015

Spider electro-combs its sticky nano-filaments January 28th, 2015

Nanoshuttle wear and tear: It's the mileage, not the age January 26th, 2015

Engineering self-assembling amyloid fibers January 26th, 2015

Photonics/Optics/Lasers

New method allows for greater variation in band gap tunability: The method can change a material's electronic band gap by up to 200 percent January 31st, 2015

Crystal light: New light-converting materials point to cheaper, more efficient solar power: University of Toronto engineers study first single crystal perovskites for new solar cell and LED applications January 30th, 2015

The laser pulse that gets shorter all by itself: Ultrashort laser pulses have become an indispensable tool for atomic and molecular research; A new technology makes creating short infrared pulses easy and cheap January 27th, 2015

New pathway to valleytronics January 27th, 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







© Copyright 1999-2015 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE