Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > University of Illinois study advances limits for ultrafast nano-devices

Ultrafast laser light creates heat transport through the nonmagnetic/ferromagnetic/nonmagnetic tri-layer. The thermal excitation in the ferromagnetic layer produces spin current in the adjacent nonmagnetic layer in a picosecond timescale.

Credit: Gyung-Min Choi
Ultrafast laser light creates heat transport through the nonmagnetic/ferromagnetic/nonmagnetic tri-layer. The thermal excitation in the ferromagnetic layer produces spin current in the adjacent nonmagnetic layer in a picosecond timescale.

Credit: Gyung-Min Choi

Abstract:
A recent study by researchers at the University of Illinois at Urbana-Champaign provides new insights on the physical mechanisms governing the interplay of spin and heat at the nanoscale, and addresses the fundamental limits of ultrafast spintronic devices for data storage and information processing.

University of Illinois study advances limits for ultrafast nano-devices

Urbana, IL | Posted on July 10th, 2014

"Electrons carry a charge as well as spin-angular momentum. In a typical charge current, electrons' spin-angular-momentum is random so there is no spin current," explained David Cahill, a professor of materials science and engineering at Illinois. "However when electrons move with a partial alignment of spin-angular-momentum, we call it spin current which is the key element for nanoscale spintronic devices.

"It is understood that spin current can rotate magnetization. In other words, we can use spin current to select "0" or "1" state of magnetic memory devices. For ultrafast operation of such nano-devices, generation of spin current in picoseconds—one trillionth of a second—a time-scale that is difficult to achieve using electrical circuits, is highly desired," Cahill added.

"In a typical electrical circuit approach, spin current is driven by voltage difference across the structure. In this work, we utilized differences in temperature to generate spin currents," explained Gyung-Min Choi, lead author of the paper, "Spin current generated by thermally-driven ultrafast demagnetization," published in Nature Communications.

"A metallic ferromagnet has three energy reservoirs: electrons, magnons, and phonons," Choi stated. "Using ultra-short laser light, we created temperature differences between these reservoirs of thermal energy for a few picoseconds. The temperature difference between electron and magnon drives an exchange of spin-angular-momentum.

"Thus, we transport spin-angular-momentum from magnons to electrons, and this transport leads to ultrafast spin current," Choi added. "We refer to this spin current as thermally-driven and believe that our results extend the emerging discipline of spin caloritronics into the regime of picosecond time scales.

The benefits of thermal generation over electric generation are two-fold, according to Choi.

"Thermal spin generation has a potential for higher efficiency than spin generation by electrical currents. Our work shows that thermal spin current can be large enough to rotate magnetization. Although the amount of spin current is still smaller than what would be required for practical applications, we show the potential of thermal generation.

"The second advantage is the fast timescale. The time scale of spin currents generated by electrical currents is limited to a few nanoseconds. In this work, we are able to create spin current with timescale of a few picoseconds. Picosecond generation of spin current is desirable for fast operation of magnetic memory devices."

###

Supported by grants from the Army Research Office and the U.S. Department of Energy Office of Basic Energy Sciences, this work was carried out in the Laser and Spectroscopy Laboratory of the Frederick Seitz Materials Research Laboratory at Illinois.

In addition to Choi and Cahill, co-authors of the paper include, Byoung-Chul Min, Center for Spintronics Research, Korea Institute of Science and Technology, Seoul, and Kyung-Jin Lee, Department of Materials Science and Engineering and KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul.

####

For more information, please click here

Contacts:
David G. Cahill

217-333-6753

Copyright © University of Illinois College of Engineering

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

Proving nanoparticles in sunscreen products August 4th, 2015

Global Carbon Nanotubes Industry 2015: Acute Market Reports August 4th, 2015

Nanoparticles Give Antibacterial Properties to Machine-Woven Carpets August 4th, 2015

Diagnosis of Salmonella Bacterium-Caused Food Poisoning by Biosensors August 3rd, 2015

Thin films offer promise for ferroelectric devices: Researchers at Tokyo Institute of Technology demystify the ferroelectric properties observed in hafnium-oxide-based thin films, revealing a potentially useful device material August 3rd, 2015

Physics

Quantum states in a nano-object manipulated using a mechanical system August 3rd, 2015

Solid state physics: Quantum matter stuck in unrest August 1st, 2015

Govt.-Legislation/Regulation/Funding/Policy

Small tilt in magnets makes them viable memory chips August 3rd, 2015

Vaccine with virus-like nanoparticles effective treatment for RSV, study finds August 3rd, 2015

MIPT researchers clear the way for fast plasmonic chips August 3rd, 2015

Nanoparticles used to breach mucus barrier in lungs: Proof-of-concept study conducted in mice a key step toward better treatments for lung diseases August 3rd, 2015

Spintronics

Spintronics: Molecules stabilizing magnetism: Organic molecules fixing the magnetic orientation of a cobalt surface/ building block for a compact and low-cost storage technology/ publication in Nature Materials July 25th, 2015

Penn researchers discover new chiral property of silicon, with photonic applications July 25th, 2015

Spintronics just got faster July 20th, 2015

Fundamental observation of spin-controlled electrical conduction in metals: Ultrafast terahertz spectroscopy yields direct insight into the building block of modern magnetic memories July 6th, 2015

Chip Technology

Small tilt in magnets makes them viable memory chips August 3rd, 2015

Better together: Graphene-nanotube hybrid switches August 3rd, 2015

MIPT researchers clear the way for fast plasmonic chips August 3rd, 2015

Thin films offer promise for ferroelectric devices: Researchers at Tokyo Institute of Technology demystify the ferroelectric properties observed in hafnium-oxide-based thin films, revealing a potentially useful device material August 3rd, 2015

Memory Technology

Small tilt in magnets makes them viable memory chips August 3rd, 2015

Controlling phase changes in solids: Controlling phase changes in solids July 29th, 2015

Reshaping the solar spectrum to turn light to electricity: UC Riverside researchers find a way to use the infrared region of the sun's spectrum to make solar cells more efficient July 27th, 2015

Spintronics: Molecules stabilizing magnetism: Organic molecules fixing the magnetic orientation of a cobalt surface/ building block for a compact and low-cost storage technology/ publication in Nature Materials July 25th, 2015

Discoveries

Proving nanoparticles in sunscreen products August 4th, 2015

Nanoparticles Give Antibacterial Properties to Machine-Woven Carpets August 4th, 2015

Small tilt in magnets makes them viable memory chips August 3rd, 2015

Better together: Graphene-nanotube hybrid switches August 3rd, 2015

Announcements

Proving nanoparticles in sunscreen products August 4th, 2015

Global Carbon Nanotubes Industry 2015: Acute Market Reports August 4th, 2015

Nanoparticles Give Antibacterial Properties to Machine-Woven Carpets August 4th, 2015

Diagnosis of Salmonella Bacterium-Caused Food Poisoning by Biosensors August 3rd, 2015

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers

Global Carbon Nanotubes Industry 2015: Acute Market Reports August 4th, 2015

Nanoparticles Give Antibacterial Properties to Machine-Woven Carpets August 4th, 2015

MIPT researchers clear the way for fast plasmonic chips August 3rd, 2015

Quantum states in a nano-object manipulated using a mechanical system August 3rd, 2015

Military

Self-assembling, biomimetic membranes may aid water filtration August 1st, 2015

Take a trip through the brain July 30th, 2015

Sol-gel capacitor dielectric offers record-high energy storage July 30th, 2015

Reshaping the solar spectrum to turn light to electricity: UC Riverside researchers find a way to use the infrared region of the sun's spectrum to make solar cells more efficient July 27th, 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