Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Lasers achieve world record tunability

 Top: real color image of the nanowire wafer with color reflecting the bandgap tuning from left to right. Bottom: lasing spectra measured at 16 spots along the length of the wafer, showing spatial wavelength tunability of 200 nm.
Top: real color image of the nanowire wafer with color reflecting the bandgap tuning from left to right. Bottom: lasing spectra measured at 16 spots along the length of the wafer, showing spatial wavelength tunability of 200 nm.

Abstract:
A single semiconductor laser chip with world-record wavelength tuning range of 200 nm—from 500 to 700 nm—has been demonstrated by a research team led by Cun-Zheng Ning, a professor in the Department of Electrical Engineering in the Ira A. Fulton School of Engineering at Arizona State Univ.

Lasers achieve world record tunability

Tempe, AZ | Posted on February 16th, 2009


Widely tunable semiconductor lasers offer a wide range of applications, ranging from spectroscopy, telecommunication, and on-chip biological and chemical detection. But achieving a widely tunable laser has been difficult due to limited lattice mismatch allowed in the standard epitaxial-based approach, since wavelength of light emission is determined by the bandgaps of semiconductors involved. Widely tunable lasers require alloy semiconductors with similarly tunable bandgaps, which are in turn determined by alloy composition, are usually limited by lattice mismatch with the chosen substrate.

With nanowire technology, the lattice mismatch limitation has been largely relaxed or removed completely. Thus it becomes possible in principle to grow alloy semiconductors of widely changing composition on a single substrate.

By carefully engineering and controlling the growth temperature and other parameters, the team was successful in growing ternary alloy CdSxSe1-x nanowires with composition x changing from 0 to 1 continuously from one end of the substrate to the other. As a result, the wafer has a continuous spatial grading of bandgaps between 1.75 eV and 2.5 eV, or in terms of the wavelength, between 500 and 700 nm.

Since the wafer is covered by nanowires that individually can act as nanolasers, numerous such nanolasers of continuously tuning wavelength are formed by a single growth on a single substrate. Under optical pumping, the team was able to show that each spot along the wafer length showing lasing behavior, as shown in the figure attached.

Such extremely wide tunable lasers are expected to have many potential applications. Tunable laser sources are vital elements for spectroscopic applications from research laboratories to molecular finger-print based field detection and sensing. They can act as multi-agent excitation light sources for florescence chip-based biological or chemical detections. They can also be used for multiplexing or de-multiplexing for chip-based communication applications. Many more applications can be explored, once such lasers are made electrically driven.

Ning's research group is currently working to extend the tunability to an even wider wavelength range and is developing several applications of such unique alloy materials in solar cells, detection, lighting and displays. In each of these applications, the unique materials capability is going to significantly improve the performance of the devices.

Team members include Dr. Ning's group at ASU, Dr. Anlian Pan, Weichang Zhou, Dr. Eunice Leong, Dr. Ruibin Liu, and Dr. Alan Chin, and his collaborator, Dr. B.S. Zou of Hunan University, China. For more information, contact Prof. Cun-Zheng Ning, (480) 965 7421; web: http://nanophotonics.asu.edu

The results are reported in a paper in a recent online version of the American Chemical Society journal Nano Letters. A log-in is required at pubs.acs.org.ezproxy1.lib.asu.edu/doi/full/10.1021/nl803456k

The research was supported by Science Foundation of Arizona and by US Army Research Office

####

For more information, please click here

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

Caught on camera -- chemical reactions 'filmed' at the single-molecule level March 22nd, 2017

Rare-earths become water-repellent only as they age March 22nd, 2017

Pulverizing e-waste is green, clean -- and cold: Rice, Indian Institute researchers use cryo-mill to turn circuit boards into separated powders March 21st, 2017

CRMGroup in Belgium uses a Deben three point bending stage in the development of new steel & coated steel products for automotive and other industrial applications March 21st, 2017

Discoveries

Caught on camera -- chemical reactions 'filmed' at the single-molecule level March 22nd, 2017

Rare-earths become water-repellent only as they age March 22nd, 2017

Pulverizing e-waste is green, clean -- and cold: Rice, Indian Institute researchers use cryo-mill to turn circuit boards into separated powders March 21st, 2017

Electro-optical switch transmits data at record-low temperatures: Operating at temperatures near absolute zero, switch could enable significantly faster data processing with lower power consumption March 20th, 2017

Announcements

Caught on camera -- chemical reactions 'filmed' at the single-molecule level March 22nd, 2017

Rare-earths become water-repellent only as they age March 22nd, 2017

Pulverizing e-waste is green, clean -- and cold: Rice, Indian Institute researchers use cryo-mill to turn circuit boards into separated powders March 21st, 2017

CRMGroup in Belgium uses a Deben three point bending stage in the development of new steel & coated steel products for automotive and other industrial applications March 21st, 2017

Photonics/Optics/Lasers

Electro-optical switch transmits data at record-low temperatures: Operating at temperatures near absolute zero, switch could enable significantly faster data processing with lower power consumption March 20th, 2017

AIM Photonics Welcomes Coventor as Newest Member: US-Backed Initiative Taps Process Modeling Specialist to Enable Manufacturing of High-Yield, High-Performance Integrated Photonic Designs March 16th, 2017

Optical fingerprint can reveal pollutants in the air: Researchers at Chalmers University of Technology have proposed a new, sophisticated method of detecting molecules with sensors based on ultra-thin nanomaterials March 15th, 2017

MIPT physicists predict the existence of unusual optical composites March 10th, 2017

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