Navigation Links
New nano-material combinations produce leap in infrared technology
Date:2/14/2012

Arizona State University researchers are finding ways to improve infrared photodetector technology that is critical to national defense and security systems, as well as used increasingly in commercial applications and consumer products.

A significant advance is reported in a recent article in the journal Applied Physics Letters. It details discovery of how infrared photodetection can be done more effectively by using certain materials arranged in specific patterns in atomic-scale structures.

It's being accomplished by using multiple ultrathin layers of the materials that are only several nanometers thick. Crystals are formed in each layer. These layered structures are then combined to form what are termed "superlattices."

Photodetectors made of different crystals absorb different wavelengths of light and convert them into an electrical signal. The conversion efficiency achieved by these crystals determines a photodectector's sensitivity and the quality of detection it provides, explains electrical engineer Yong-Hang Zhang.

The unique property of the superlattices is that their detection wavelengths can be broadly tuned by changing the design and composition of the layered structures. The precise arrangements of the nanoscale materials in superlattice structures helps to enhance the sensitivity of infrared detectors, Zhang says.

Zhang is a professor in the School of Electrical, Computer and Energy Engineering, one of ASU's Ira A. Fulton Schools of Engineering. He is leading the work on infrared technology research in ASU's Center for Photonics Innovation. More information can be found at the center's Optoelectronics Group website at http://asumbe.eas.asu.edu/

Additional research in this area is being supported by a grant from the Air Force Office of Scientific Research and a new Multidisciplinary University Research Initiative (MURI) program established by the U.S. Army Research Office. ASU is a partner in the program led by the University of Illinois at Urbana-Champaign.

The MURI program is enabling Zhang's group to accelerate its work by teaming with David Smith, a professor in the Department of Physics in ASU's College of Liberal Arts and Sciences, and Shane Johnson, a senior research scientist in the ASU's engineering schools.

The team is using a combination of indium arsenide and indium arsenide antimonide to build the superlattice structures. The combination allows devices to generate photo electrons necessary to provide infrared signal detection and imaging, says Elizabeth Steenbergen, an electrical engineering doctoral student who performed experiments on the supperlattice materials with collaborators at the Army Research Lab.

"In a photodetector, light creates electrons. Electrons emerge from the photodetector as electrical current. We read the magnitude of this current to measure infrared light intensity," she says.

"In this chain, we want all of the electrons to be collected from the detector as efficiently as possible. But sometimes these electrons get lost inside the device and are never collected," says team member Orkun Cellek, an electrical engineering postdoctoral research associate.

Zhang says the team's use of the new materials is reducing this loss of optically excited electrons, which increases the electrons' carrier lifetime by more than 10 times what has been achieved by other combinations of materials traditionally used in the technology. Carrier lifetime is a key parameter that has limited detector efficiency in the past.

Another advantage is that infrared photodetectors made from these superlattice materials don't need as much cooling. Such devices are cooled as a way of reducing the amount of unwanted current inside the devices that can "bury" electrical signals, Zhang says.

The need for less cooling reduces the amount of power needed to operate the photodetectors, which will make the devices more reliable and the systems more cost effective.

Researchers say improvements can still be made in the layering designs of the intricate superlattice structures and in developing device designs that will allow the new combinations of materials to work most effectively.

The advances promise to improve everything from guided weaponry and sophisticated surveillance systems to industrial and home security systems, the use of infrared detection for medical imaging and as a road-safety tool for driving at night or during sand storms or heavy fog.

"You would be able to see things ahead of you on the road much better than with any headlights," Cellek says.


'/>"/>

Contact: Joe Kullman
joe.kullman@asu.edu
480-965-8122
Arizona State University
Source:Eurekalert

Related biology technology :

1. Researchers design new graphene-based, nano-material with magnetic properties
2. Carbon-Based Nano-Materials and Devices Conference
3. Volatile Economy / Fundraising Challenges Encourage Business Combinations Among Biotech Companies According to New Survey from CPA Firm Rothstein Kass
4. Researchers create atlas of transcription factor combinations
5. Launch of Two New Platforms for Microplate Analysis Expands Reader Portfolio and Ensures Molecular Devices Readers Meet all Combinations of Customer Needs
6. Pioneering IVF Technique Produces Region's First Pregnancy
7. Northwestern chemists take gold, mass-produce Beijing Olympic logo
8. Early-Bird Registration Ends this Week for 10th Annual Quality Excellence Conference: How Process Improvement Leaders Produce Profits in Recessions
9. Professor-turned-producer learns the movie biz
10. SemBioSys eligible to proceed with Phase I/II plant-produced insulin trial after submission of IND
11. Martek to be the Sole Source Supplier of DHA and ARA for Infant Formulas Produced By Grupo Ricap
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/22/2017)... Bahama (PRWEB) , ... March 21, 2017 , ... Okyanos ... educational seminar as part of their live events series, “Stem Cell Therapy: The Next ... cell facility under the 2013 Stem Cell Research and Therapy Act, Okyanos ...
(Date:3/22/2017)... ... March 21, 2017 , ... Benchworks CEO ... Executive Officer Forum on March 23-24 in San Diego. The event is a ... diagnostic industries. , Benchworks Vice President Christian Meyer will also participate in the ...
(Date:3/22/2017)... ... , ... The Conference Forum has announced the launch of the 5th Annual ... 2017, at the Colonnade Hotel in Boston, MA. The CMO Summit is the only ... and support. , “The Chief Medical Officer faces a unique set of challenges at ...
(Date:3/22/2017)... and CARDIFF, UK (PRWEB) , ... March 21, 2017 , ... ... flow and tissue oxygenation, is being explored as a way to track the brain’s ... study on tonic pain activation by cold pressor test ,” published today in the ...
Breaking Biology Technology:
(Date:2/26/2017)... , Feb. 25, 2017  Securus Technologies, a ... solutions for public safety, investigation, corrections and monitoring, ... and Reentry. "Too often, too many ... and county jails are trying to tackle this ... and friends and family members. While significant steps are ...
(Date:2/21/2017)... and PORTLAND, Ore. , ... and the Avamere Family of Companies (Avamere Health Services, ... announced a six-month research study that will apply the ... eldercare at senior living and health centers. By analyzing ... hopes to gain insights into physical and environmental conditions, ...
(Date:2/14/2017)... N.C. , Feb. 14, 2017  Wake Forest ... M.D., as its new chief executive officer (CEO). Freischlag ... CEO John D. McConnell , M.D., who last ... position at the Medical Center, after leading it since ... the full scope of Wake Forest Baptist,s academic health ...
Breaking Biology News(10 mins):