Back home   |   Bookmark   |   Start page   |   Site map    
Services
News
Channels
Home & Family
Leisure
Technology
Business
Science
Site Search
Free email




Toward terahertz detectors on a single, conventional chip

Theallineed.com
(NC&T/UB) But because signals in the terahertz range have traditionally been incompatible with conventional microelectronics, this potential has been slow to realize.

Now, University at Buffalo researchers and their collaborators at other institutions have been awarded a four-year, $1.2 million National Science Foundation grant, under the NSF Nanoscale Interdisciplinary Research Teams (NIRT) initiative, to develop semiconductor-based terahertz detectors that can be integrated seamlessly with conventional electronics. The grant is one of only 10 that the NSF has funded from more than 400 applications received.

Applications for the detectors are wide-ranging: from more secure signal-processing in telecommunications and precise imaging of real-time protein-binding in pharmaceutical research, to more powerful homeland defense technologies.

"We are developing new types of sensitive, electro-magnetic detectors that can be used at frequencies where no reliable technology currently exists," said Andrea Markelz, Ph.D., principal investigator and associate professor of physics in the UB College of Arts and Sciences.

In research being conducted by Andrea Markelz and Jonathan Bird, the gray and yellow regions create a nanowire device that detects terahertz radiation emitted by a targeted substance. (Photo: U. at Buffalo)
These detectors, which could be integrated into large-scale arrays, would provide sophisticated signal processing capabilities, providing widely tunable response frequency, low power consumption and enhanced sensitivity.

Among the devices the UB team will develop are those based on quantum dot arrays and hybrid devices. A quantum point contact terahertz detector likely will be furthest along in development at the end of the grant, according to Markelz.

"The biggest advantage to this quantum point contact terahertz detector that we are developing is that it will provide spectral information, revealing many wavelengths at once, allowing for far more precise distinctions among similar objects," she said.

Such a powerful detector could assist potentially in detecting illegal or dangerous materials hidden in baggage or parcels; the terahertz range of the spectrum also is especially useful in detecting the binding of inhibitors with protein targets, allowing for rapid drug screening.

Markelz's expertise lies in characterizations of terahertz optical systems and materials at these frequencies while co-principal investigator Jonathan Bird, Ph.D., professor of electrical engineering in the UB School of Engineering and Applied Sciences, focuses on fabrication and characterization of semiconductor nanodevices.

"Interdisciplinary collaborations of this sort will enable the translation of theoretical and experimental physics to design engineering of new and useful detectors for homeland security applications among others," said Jorge José, Ph.D., UB vice president for research. "This is exactly the type of outcome we are hoping for from the university's UB 2020 strategic strength initiative on integrated nanostructured systems."

Related research by Markelz and Bird will be published soon in Applied Physics Letters.

Bird, who studies the behavior of electrons in nanostructures, noted that the fundamental science of terahertz radiation will be enhanced by the research.

"We will gain a detailed understanding of how the electrical properties of semiconductor nanodevices are modified in the presence of terahertz radiation," he said.

This NIRT collaboration especially is noteworthy because it provides an opportunity for experimental physicists and theoretical physicists, as well as electrical engineers, to tackle the same scientific problem.

"What is so wonderful about this grant is that the experimentalists will be able to say to the theorists, 'This is what we don't understand' and the theorists can then reconsider their models, based on what's happening with the real-world device," Markelz said.

The grant provides important avenues for outreach to underserved populations, since the theorists are based at Queens College and Kingsborough Community College, units of the City University of New York, which do not have graduate programs. The collaboration will provide state-of-the-art research opportunities to students at these institutions and encourage them to pursue higher degrees in science and engineering.

It also allows Markelz to continue GGems (Girls and Guys Exploring Math and Science), an educational program for high school students she launched with her NSF Career award that involves UB, the Buffalo Public Schools and the Buffalo Museum of Science, and aims to attract more females and other under-represented groups to the sciences.

Other collaborators on the research are based at the University of California at Santa Barbara, the Institute of Physical and Chemical Research (RIKEN, Japan) and Sandia National Laboratories.

Preliminary work on this research was funded through an Interdisciplinary Research and Creative Activities Fund (IRCAF) grant through the UB Office of the Vice President for Research.

The University at Buffalo is a premier research-intensive public university, the largest and most comprehensive campus in the State University of New York.

About the Author
©2006 All rights reserved

More articles
Carbon nanotubes
Heavy metals
Turbine blades
IAECS prototype
Solar flares
Mit's intelligent aircraft fly
Solar flares
Study shows internet to be resilient against terror attack
lCD manufacturing
Morphed image
Better battery
Single-pixel camera
Terahertz detectors
The quantum cryptographic
Grass holds
Hybrid nanoparticles
Public Internet lines
Reduce herbicide use
Dielectric dead layer
Nanoparticle assembly
Quotes
If I work incessantly to the last, nature owes me another form of existence when the present one collapses. -- Goethe, 1829

If a few idiots want to risk their necks flying across the country thats fine, but nothing will ever replace trains.


Writers
If you are a writer and want to see your article published at Theallineed.com, just click here to submit.

Info
Today...
In the news...
Poverty reflected in children's schools as well as in the home
The report, which is based on a survey of 7,600 schools in 11 countries in Latin America, Asia and North Africa, reveals a particularly glaring gap between the resources available to urban and rural schools.
Do you think that Judge should be nominated for the United States Supreme Court?
Yes, the President picked him and the Senate should just confirm him
Yes, he will help put a stop to activist rulings
No, he will royally srcew up the country
No, silent nominations never turn out well
 
Things to ponder
If someone invented instant water, what would they mix it with?

Did you know...
Atomic bombs release 50% energy as blast, 35% as heat and 15% as nuclear radiation.

Quote of the day
Silent gratitude isn't very much use to anyone.
Gertrude Stein

Featured article
Fabulous Fremantle: Western Australia's shoppers paradise
Fremantle has its High Street shopping scene with Essex Street, Market Street, and High Street all offering fine shopping options. Fremantle is home to the usual big department stores located around the malls and King's Square.

 
© 2002 - 2007 Lexur