Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Scientists put the squeeze on electron spins

Abstract:
By squeezing the crystal in a controlled manner, and without applying magnetic fields, the researchers were able to watch the electron spins rotate (or precess) as they flow through the crystal.

Scientists put the squeeze on electron spins

Los Alamos, N.M. | June 16, 2005

University of California scientists working at Los Alamos National Laboratory have developed a novel method for controlling and measuring electron spins in semiconductor crystals of GaAs (gallium arsenide). The work suggests an alternative -- and perhaps even superior -- method of spin manipulation for future generations of "semiconductor spintronic" devices.

In research published in today's issue of the scientific journal Physical Review Letters, Scott Crooker and Darryl Smith describe their use of a scanning optical microscope to acquire two-dimensional images of spin-polarized electrons flowing in semiconductor crystals mounted on an optical cryostat while using a miniature "cryogenic vise" to apply gentle pressure. By squeezing the crystal in a controlled manner, and without applying magnetic fields, the researchers were able to watch the electron spins rotate (or precess) as they flow through the crystal.

According to Crooker, "electrons, in addition to their negative electronic charge, also possess a magnetic "spin". That is, each electron behaves like a little bar magnet, with north and south poles. Electron spins in semiconductors are typically manipulated by applying a magnetic field, but we've found we can do the same thing, in a controlled fashion, using the "vise". And, the resulting degree of spatial spin coherence is remarkably more robust compared to the spin precession induced by a magnetic field."

The cryogenic vise operates at only a few degrees above absolute zero (4 degrees Kelvin) and can be used to intentionally tip, rotate, and flip the electron spins. The research was conducted at the Pulsed Field Facility of the National High Magnetic Field Laboratory (NHMFL) at Los Alamos.

The research was funded by Los Alamos Laboratory-Directed Research and Development (LDRD) funding and the Defense Advanced Research Project Agency's SPins IN Semiconductors (SPINS) Program, which is designed to encourage research to exploit the spin degree of freedom of the electron and create revolutionary electronic devices with the potential to be very fast at very low power.

Alex H. Lacerda, Director of NHMFL-Los Alamos, states, "This work is an excellent example of how the LDRD program engenders strong inter-divisional relationships and enduring experimental-theoretical collaborations at Los Alamos for the pursuit of basic science."

The research fits into a broader area of expertise that Los Alamos National Laboratory maintains in the field of atomic physics in general, and spintronics research in particular.

####

About Los Alamos National Laboratory:
Los Alamos National Laboratory is operated by the University of California for the National Nuclear Security Administration of the U.S. Department of Energy and works in partnership with NNSA's Sandia and Lawrence Livermore national laboratories to support NNSA in its mission. Los Alamos enhances global security by ensuring the safety and reliability of the U.S. nuclear deterrent, developing technologies to reduce threats from weapons of mass destruction, and solving problems related to defense, energy, environment, infrastructure, health and national security concerns.

Contact:
Todd Hanson
tahanson@lanl.gov
(505) 665-2085 (04-147)

Copyright © Los Alamos National Laboratory

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

Epoxy compound gets a graphene bump: Rice scientists combine graphene foam, epoxy into tough, conductive composite November 14th, 2018

Optimization of alloy materials: Diffusion processes in nano particles decoded November 13th, 2018

Arrowhead Pharmaceuticals Presents Late-Breaking Preliminary Clinical Data on ARO-HBV at Liver Meeting® 2018 November 9th, 2018

Unlocking the Secrets of Metal-Insulator Transitions: X-ray photon correlation spectroscopy at NSLS-II's CSX beamline used to understand electrical conductivity transitions in magnetite November 8th, 2018

Spintronics

2-D magnetism: Atom-thick platforms for energy, information and computing research: Scientists say the tiny 'spins' of electrons show potential to one day support next-generation innovations in many fields October 31st, 2018

Graphene controls surface magnetism at room temperature October 8th, 2018

New devices based on rust could reduce excess heat in computers: Physicists explore long-distance information transmission in antiferromagnetic iron oxide September 14th, 2018

Energy-efficient spin current can be controlled by magnetic field and temperature: SCMR effect simplifies the design of fundamental spintronic components August 20th, 2018

Announcements

Epoxy compound gets a graphene bump: Rice scientists combine graphene foam, epoxy into tough, conductive composite November 14th, 2018

Optimization of alloy materials: Diffusion processes in nano particles decoded November 13th, 2018

GLOBALFOUNDRIES, indie Semiconductor Deliver Performance-Enhanced Microcontrollers for Automotive Applications: 55nm LPx platform, with SST’s highly reliable embedded SuperFlash®, increases performance and energy efficiency for automotive applications November 13th, 2018

GLOBALFOUNDRIES, indie Semiconductor Deliver Performance-Enhanced Microcontrollers for Automotive Applications: 55nm LPx platform, with SST’s highly reliable embedded SuperFlash®, increases performance and energy efficiency for automotive applications November 13th, 2018

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project