Nanotechnology Now







Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Physicists measure current-induced torque in nonvolatile magnetic memory devices


The geometry of a magnetic tunnel junction.
The geometry of a magnetic tunnel junction.

Abstract:
Tomorrow's nonvolatile memory devices -- computer memory that can retain stored information even when not powered -- will profoundly change electronics, and Cornell researchers have discovered a new way of measuring and optimizing their performance.

Physicists measure current-induced torque in nonvolatile magnetic memory devices

Ithaca, NY | Posted on March 9th, 2011

Using a very fast oscilloscope, researchers led by Dan Ralph, the Horace White Professor of Physics, and Robert Buhrman, the J.E. Sweet Professor of Engineering, have figured out how to quantify the strength of current-induced torques used to write information in memory devices called magnetic tunnel junctions. The results were published online Feb. 27 in the journal Nature Physics.

Magnetic tunnel junctions are memory storage devices made of a sandwich of two ferromagnets with a nanometers-thick oxide insulator in between. The electrical resistance of the device is different for parallel and nonparallel orientations of the magnetic electrodes, so that these two states create a nonvolatile memory element that doesn't require electricity for storing information. An example of nonvolatile memory today is flash memory, but that is a silicon-based technology subject to wearing out after repeated writing cycles, unlike magnetic memory.

What has held back magnetic memory technology is that it has required magnetic fields to switch the magnetic states -- that is, to write information. This limits their size and efficiency because magnetic fields are long-ranged and relatively weak, so large currents and thick wires are needed to generate a large-enough field to switch the device.

The Cornell researchers are studying a new generation of magnetic devices that can write information without using magnetic fields. Instead, they use a mechanism called "spin torque," which arises from the idea that electrons have a fundamental spin (like a spinning top). When the electrons interact with the magnets in the tunnel junctions, they transfer some of their angular momentum. This can provide a very strong torque per unit current, and has been demonstrated to be at least 500 times more efficient than using magnetic fields to write magnetic information, Ralph said.

To measure these spin torques, the researchers used an oscilloscope in a shared facility operated by Cornell's Center for Nanoscale Systems. They applied torque to the magnetic tunnel junctions using an alternating current and measured the amplitude of resistance oscillations that resulted. Since the resistance depends on the relative orientation of the two magnets in the tunnel junction, the size of the resistance oscillations could be related directly to the amplitude of the magnetic motion, and hence to the size of the torque.

The researchers hope such experiments will help industry make better nonvolatile memory devices by understanding exactly how to structure them, and also, what materials would best be used as the oxide insulators and the ferromagnets surrounding them.

The work was supported by the National Science Foundation, the Army Research Office and the Office of Naval Research, and included collaborators Chen Wang, graduate student and first author; graduate student Yong-Tao Cui; and Jordan A. Katine from Hitachi Global Storage Technologies.

####

For more information, please click here

Contacts:
Media Contact:
Blaine Friedlander
(607) 254-8093


Anne Ju
(607) 255-9735


Chronicle Online
312 College Ave.
Ithaca, NY 14850
607.255.4206

Copyright © Cornell 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

News and information

Graphene Shows Promise In Eradication Of Stem Cancer Cells March 1st, 2015

Novel Method to Determine Optical Purity of Drug Components March 1st, 2015

Scientific breakthrough in rechargeable batteries: Researchers from Singapore and Québec Team Up to Develop Next-Generation Materials to Power Electronic Devices and Electric Vehicles February 28th, 2015

First detailed microscopy evidence of bacteria at the lower size limit of life: Berkeley Lab research provides comprehensive description of ultra-small bacteria February 28th, 2015

Untangling DNA with a droplet of water, a pipet and a polymer: With the 'rolling droplet technique,' a DNA-injected water droplet rolls like a ball over a platelet, sticking the DNA to the plate surface February 27th, 2015

Physics

Moving molecule writes letters: Caging of molecules allows investigation of equilibrium thermodynamics February 27th, 2015

Real-time observation of bond formation by using femtosecond X-ray liquidography February 26th, 2015

Warming up the world of superconductors: Clusters of aluminum metal atoms become superconductive at surprisingly high temperatures February 25th, 2015

Govt.-Legislation/Regulation/Funding/Policy

First detailed microscopy evidence of bacteria at the lower size limit of life: Berkeley Lab research provides comprehensive description of ultra-small bacteria February 28th, 2015

Warming up the world of superconductors: Clusters of aluminum metal atoms become superconductive at surprisingly high temperatures February 25th, 2015

SUNY Poly CNSE Researchers and Corporate Partners to Present Forty Papers at Globally Recognized Lithography Conference: SUNY Poly CNSE Research Group Awarded Both ‘Best Research Paper’ and ‘Best Research Poster’ at SPIE Advanced Lithography 2015 forum February 25th, 2015

European roadmap for graphene science and technology published February 25th, 2015

Spintronics

Insight into inner magnetic layers: Measurements at BESSY II have shown how spin filters forming within magnetic sandwiches influence tunnel magnetoresistance -- results that can help in designing spintronic component- February 17th, 2015

A new spin on spintronics: Michigan team tests radiation-resistant spintronic material, possibly enabling electronic devices that will work in harsh environments February 17th, 2015

Nanoscale Mirrored Cavities Amplify, Connect Quantum Memories: Advance could lead to quantum computing and the secure transfer of information over long-distance fiber optic networks January 28th, 2015

Piezoelectricity in a 2-D semiconductor: Berkeley Lab researchers discovery of piezoelectricty in molybdenum disulfide holds promise for future MEMS December 22nd, 2014

Chip Technology

New nanowire structure absorbs light efficiently: Dual-type nanowire arrays can be used in applications such as LEDs and solar cells February 25th, 2015

SUNY Poly CNSE Researchers and Corporate Partners to Present Forty Papers at Globally Recognized Lithography Conference: SUNY Poly CNSE Research Group Awarded Both ‘Best Research Paper’ and ‘Best Research Poster’ at SPIE Advanced Lithography 2015 forum February 25th, 2015

Ultra-thin nanowires can trap electron 'twisters' that disrupt superconductors February 24th, 2015

Silicon Catalyst Announces Partnership With imec to Support Semiconductor Start-Ups February 23rd, 2015

Memory Technology

Insight into inner magnetic layers: Measurements at BESSY II have shown how spin filters forming within magnetic sandwiches influence tunnel magnetoresistance -- results that can help in designing spintronic component- February 17th, 2015

Dance of the nanovortices February 2nd, 2015

Nano - "Green" metal oxides ... January 13th, 2015

Quantum optical hard drive breakthrough January 8th, 2015

Discoveries

Graphene Shows Promise In Eradication Of Stem Cancer Cells March 1st, 2015

Novel Method to Determine Optical Purity of Drug Components March 1st, 2015

First detailed microscopy evidence of bacteria at the lower size limit of life: Berkeley Lab research provides comprehensive description of ultra-small bacteria February 28th, 2015

Moving molecule writes letters: Caging of molecules allows investigation of equilibrium thermodynamics February 27th, 2015

Announcements

Graphene Shows Promise In Eradication Of Stem Cancer Cells March 1st, 2015

Novel Method to Determine Optical Purity of Drug Components March 1st, 2015

Scientific breakthrough in rechargeable batteries: Researchers from Singapore and Québec Team Up to Develop Next-Generation Materials to Power Electronic Devices and Electric Vehicles February 28th, 2015

First detailed microscopy evidence of bacteria at the lower size limit of life: Berkeley Lab research provides comprehensive description of ultra-small bacteria February 28th, 2015

Military

Simulating superconducting materials with ultracold atoms: Rice physicists build superconductor analog, observe antiferromagnetic order February 23rd, 2015

Perfect colors, captured with one ultra-thin lens: No need for color correction -- Harvard physicists' flat optics, using nanotechnology, get it right the first time February 19th, 2015

Penn researchers develop new technique for making molybdenum disulfide: Extra control over monolayer material with advantages over graphene February 19th, 2015

New nanogel for drug delivery: Self-healing gel can be injected into the body and act as a long-term drug depot February 19th, 2015

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 1999-2015 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE