Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Quantum Device Traps, Detects and Manipulates the Spin of Single Electrons

A semiconductor developed by UB engineers provides a novel way to trap, detect and manipulate electron spin.
A semiconductor developed by UB engineers provides a novel way to trap, detect and manipulate electron spin.

Abstract:
A novel device, developed by a team led by University at Buffalo engineers, simply and conveniently traps, detects and manipulates the single spin of an electron, overcoming some major obstacles that have prevented progress toward spintronics and spin-based quantum computing.

Quantum Device Traps, Detects and Manipulates the Spin of Single Electrons

Buffalo, NY | Posted on September 28th, 2007

Published online this week in Physical Review Letters, the research paper brings closer to reality electronic devices based on the use of single spins and their promise of low-power/high-performance computing.

"The task of manipulating the spin of single electrons is a hugely daunting technological challenge that has the potential, if overcome, to open up new paradigms of nanoelectronics," said Jonathan P. Bird, Ph.D., professor of electrical engineering in the UB School of Engineering and Applied Sciences and principal investigator on the project. "In this paper, we demonstrate a novel approach that allows us to easily trap, manipulate and detect single-electron spins, in a scheme that has the potential to be scaled up in the future into dense, integrated circuits."

While several groups have recently reported the trapping of a single spin, they all have done so using quantum dots, nanoscale semiconductors that can only demonstrate spin trapping in extremely cold temperatures, below 1 degree Kelvin.

The cooling of devices or computers to that temperature is not routinely achievable, Bird said, and it makes systems far more sensitive to interference.

The UB group, by contrast, has trapped and detected spin at temperatures of about 20 degrees Kelvin, a level that Bird says should allow for the development of a viable technology, based on this approach.

In addition, the system they developed requires relatively few logic gates, the components in semiconductors that control electron flow, making scalability to complex integrated circuits very feasible.

The UB researchers achieved success through their innovative use of quantum point contacts: narrow, nanoscale constrictions that control the flow of electrical charge between two conducting regions of a semiconductor.

"It was recently predicted that it should be possible to use these constrictions to trap single spins," said Bird. "In this paper, we provide evidence that such trapping can, indeed, be achieved with quantum point contacts and that it may also be manipulated electrically."

The system they developed steers the electrical current in a semiconductor by selectively applying voltage to metallic gates that are fabricated on its surface.

These gates have a nanoscale gap between them, Bird explained, and it is in this gap where the quantum point contact forms when voltage is applied to them.

By varying the voltage applied to the gates, the width of this constriction can be squeezed continuously, until it eventually closes completely, he said.

"As we increase the charge on the gates, this begins to close that gap," explained Bird, "allowing fewer and fewer electrons to pass through until eventually they all stop going through. As we squeeze off the channel, just before the gap closes completely, we can detect the trapping of the last electron in the channel and its spin."

The trapping of spin in that instant is detected as a change in the electrical current flowing through the other half of the device, he explained.

"One region of the device is sensitive to what happens in the other region," he said.

Now that the UB researchers have trapped and detected single spin, the next step is to work on trapping and detecting two or more spins that can communicate with each other, a prerequisite for spintronics and quantum computing.

Co-authors on the paper are Youngsoo Yoon, Ph.D., a UB doctoral student in electrical engineering; L. Mourokh of Queens College and the College of Staten Island of the City University of New York; T. Morimoto, N. Aoki and Y. Ochiai of Chiba University in Japan; and J. L. Reno of Sandia National Laboratories.

The research was funded by the U.S. Department of Energy. Bird, who also has received funding from the UB Office of the Vice President for Research, was recruited to UB with a faculty recruitment grant from the New York State Office of Science, Technology and Academic Outreach (NYSTAR).

####

About University of Buffalo
The University at Buffalo is a premier research-intensive public university, the largest and most comprehensive campus in the State University of New York. UB's more than 28,000 students pursue their academic interests through more than 300 undergraduate, graduate and professional degree programs. Founded in 1846, the University at Buffalo is a member of the Association of American Universities.

For more information, please click here

Contacts:
Ellen Goldbaum



716-645-5000 ext 1415

Copyright © University of Buffalo

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

Spintronics

ICN2 researchers compute unprecedented values for spin lifetime anisotropy in graphene November 17th, 2017

Spin current detection in quantum materials unlocks potential for alternative electronics October 15th, 2017

Rice U. lab surprised by ultraflat magnets: Researchers create atom-thick alloys with unanticipated magnetic properties October 13th, 2017

A Sea of Spinning Electrons: Rutgers-led discovery could spawn a wave of new electronic devices October 2nd, 2017

Quantum Computing

Spin current detection in quantum materials unlocks potential for alternative electronics October 15th, 2017

Quantum manipulation power for quantum information processing gets a boost: Improving the efficiency of quantum heat engines involves reducing the number of photons in a cavity, ultimately impacting quantum manipulation power October 14th, 2017

Quantum communications bend to our needs: By changing the wavelengths of entangled photons to those used in telecommunications, researchers see quantum technology take a major leap forward September 28th, 2017

Physicists develop new recipes for design of fast single-photon gun Physicists develop high-speed single-photon sources for quantum computers of the future September 21st, 2017

Discoveries

ICN2 researchers compute unprecedented values for spin lifetime anisotropy in graphene November 17th, 2017

Math gets real in strong, lightweight structures: Rice University researchers use 3-D printers to turn century-old theory into complex schwarzites November 16th, 2017

The stacked color sensor: True colors meet minimization November 16th, 2017

Counterfeits and product piracy can be prevented by security features, such as printed 3-D microstructures: Forgeries and product piracy are detrimental to society and industry -- 3-D microstructures can increase security -- KIT researchers develop innovative fluorescent 3-D stru November 15th, 2017

Announcements

ICN2 researchers compute unprecedented values for spin lifetime anisotropy in graphene November 17th, 2017

Math gets real in strong, lightweight structures: Rice University researchers use 3-D printers to turn century-old theory into complex schwarzites November 16th, 2017

The stacked color sensor: True colors meet minimization November 16th, 2017

Nanometrics to Participate in the 6th Annual NYC Investor Summit 2017 November 16th, 2017

Quantum nanoscience

'Find the Lady' in the quantum world: International team of researchers presents method for quantum-mechanical swapping of positions October 18th, 2017

What can be discovered at the junction of physics and chemistry October 6th, 2017

Energy against the current on a quantum scale, without contradicting the laws of physics: A piece of research in which the UPV/EHU-University of the Basque Country has participated confirms that merely observing a flow of energy or particles can change its direction October 6th, 2017

Enhancing the sensing capabilities of diamonds with quantum properties: A simple method can give diamonds the special properties needed for quantum applications such as sensing magnetic fields September 24th, 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