Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > A new spin on silicon

Abstract:
Chip makers could get the benefits of spintronics without having to abandon silicon

A new spin on silicon

August 02, 2005

For about 40 years, the semiconductor industry has been able to continually shrink the electronic components on silicon chips, packing ever more performance into computers. Now, fundamental physical limits to current technology have the industry scouring the research world for an alternative. In a paper published in the Aug. 1 online edition of Physical Review Letters (PRL), Stanford University physicists present "orbitronics," an alternative to conventional electronics that could someday allow engineers to skirt a daunting limit while still using cheap, familiar silicon.

"The miniaturization of the present-day chips is limited by power dissipation," says Shoucheng Zhang, a professor of physics, applied physics and, by courtesy, electrical engineering, who co-authored the PRL study. "Up to 40 percent of the power in circuits is being lost in heat leakage," which he says will eventually make miniaturization a forbidding task.

Spintronics

In recent years, the search for an alternative to conventional semiconductors has resulted in the discovery of a nanotechnology called "spintronics," which uses a property of electrons called "spin" to produce a novel kind of current that integrated circuits can process as information. Spin refers to how an electron rotates on its axis, similar to the rotation of the Earth. In 2003, Zhang and colleagues at the University of Tokyo showed that producing and manipulating a current of aligned electron spins with an electric field would not involve any losses to heat—a technique they called spintronics.

Zhang now co-directs the IBM-Stanford Spintronic Science and Applications Center, along with Stanford electrical engineering Professor James Harris and IBM research fellow Stuart Parkin. The center, established in 2004, is investigating many applications of spintronics, including room-temperature superconductors and quantum computers.

Playing the angles

For all its potential, a drawback of spintronics is that it doesn't work very well with lighter atoms, such as silicon, which the microelectronics industry prefers. Enter Zhang's new research. In the PRL paper, he and graduate students B. Andrei Bernevig and Taylor L. Hughes show how, in theory, silicon could be used in a related technology they dubbed orbitronics. By using orbitronics, Zhang says, computer chip makers could get the benefits of spintronics without having to abandon silicon.

Both orbitronics and spintronics involve a physical quantity called "angular momentum," a property of any mass that moves around a fixed position, be it a tetherball or an electron.

Like an electric current, which is the flow of negatively charged electrons in a conventional integrated circuit, an orbital current would consist of a flow of electrons with their angular momenta aligned in an orbitronic circuit. "If you push electrons forward with an electric field, then an orbital current will be generated perpendicular to this electric current," Zhang says. "It will not carry charge, but will carry orbital angular momentum perpendicular to the direction in which the electrons are moving."

Therefore, he explains, with orbitronics, silicon would still be able to provide a useful current with no losses to heat at room temperature. Some alternative technologies require cold temperatures that are difficult and expensive to maintain, he adds.

From theory to application

The authors point out that orbitronics still has a long way to go to become an applied technology in the semiconductor industry. "This is so new," Zhang acknowledges. "When something is first discovered it is hard to say. There are many difficulties in the practical world."

Harris agrees, noting that spintronics will likely still take decades to become a mature commercial technology. "It's not going to happen immediately, even if we are incredibly successful," he says.

But if orbitronics turns out to indeed be an economically feasible technology to manufacture, it will be a boon to the industry to stick with silicon, Zhang says. "There is a huge, huge investment in processing silicon," he says. "We don't want to switch overnight to a new material."

David Orenstein is the Communications and Public Relations Manager for the School of Engineering.

####


Editor Note: The study, "Orbitronics: The Intrinsic Orbital Current in p-Doped Silicon," appears in the Aug. 1 online edition of Physical Review Letters at prl.aps.org.

Relevant Web URLs:
S.C.Zhang Group
IBM-Stanford Spintronic Science and Applications Center
Physical Review Letters

Contact:
Mark Shwartz
Stanford News Service
(650) 736-2245
davidjo@stanford.edu

Comment:
Andrei Bernevig
Department of Physics
(650) 724-8054

Copyright © Stanford 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

Possible Futures

Imaging electric charge propagating along microbial nanowires October 20th, 2014

Superconducting circuits, simplified: New circuit design could unlock the power of experimental superconducting computer chips October 18th, 2014

Nanocoatings Market By Product Is Expected To Reach USD 8.17 Billion By 2020: Grand View Research, Inc. October 15th, 2014

Perpetuus Carbon Group Receives Independent Verification of its Production Capacity for Graphenes at 140 Tonnes per Annum: Perpetuus Becomes the First Manufacturer in the Sector to Allow Third Party Audit October 7th, 2014

Chip Technology

Sussex physicists find simple solution for quantum technology challenge October 28th, 2014

Watching the hidden life of materials: Ultrafast electron diffraction experiments open a new window on the microscopic world October 27th, 2014

Breakthrough in molecular electronics paves the way for DNA-based computer circuits in the future: DNA-based programmable circuits could be more sophisticated, cheaper and simpler to make October 27th, 2014

QuantumWise guides the semiconductor industry towards the atomic scale October 24th, 2014

Nanoelectronics

Breakthrough in molecular electronics paves the way for DNA-based computer circuits in the future: DNA-based programmable circuits could be more sophisticated, cheaper and simpler to make October 27th, 2014

NIST offers electronics industry 2 ways to snoop on self-organizing molecules October 22nd, 2014

Materials for the next generation of electronics and photovoltaics: MacArthur Fellow develops new uses for carbon nanotubes October 21st, 2014

Crystallizing the DNA nanotechnology dream: Scientists have designed the first large DNA crystals with precisely prescribed depths and complex 3D features, which could create revolutionary nanodevices October 20th, 2014

Announcements

First Observation of Electronic Structure in Ag-Rh Alloy Nanoparticles Having Hydrogen Absorbing: Storage Property –Attempting to solve the mystery of why Ag-Rh alloy nanoparticles have a similar property to Pd– October 30th, 2014

Iranians Present Model to Predict Photocatalytic Process in Removal of Pollutants October 30th, 2014

Production of Biocompatible Polymers in Iran October 30th, 2014

Amorphous Coordination Polymer Particles as alternative to classical nanoplatforms for nanomedicine October 30th, 2014

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 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE