Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

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

Construction of practical quantum computers radically simplified: Scientists invent ground-breaking new method that puts quantum computers within reach December 5th, 2016

Shape matters when light meets atom: Mapping the interaction of a single atom with a single photon may inform design of quantum devices December 4th, 2016

UTSA study describes new minimally invasive device to treat cancer and other illnesses: Medicine diffusion capsule could locally treat multiple ailments and diseases over several weeks December 3rd, 2016

Novel Electrode Structure Provides New Promise for Lithium-Sulfur Batteries December 3rd, 2016

Physics

Shape matters when light meets atom: Mapping the interaction of a single atom with a single photon may inform design of quantum devices December 4th, 2016

Deep insights from surface reactions: Researchers use Stampede supercomputer to study new chemical sensing methods, desalination and bacterial energy production December 2nd, 2016

Govt.-Legislation/Regulation/Funding/Policy

Construction of practical quantum computers radically simplified: Scientists invent ground-breaking new method that puts quantum computers within reach December 5th, 2016

Shape matters when light meets atom: Mapping the interaction of a single atom with a single photon may inform design of quantum devices December 4th, 2016

Research Study: MetaSOLTM Shatters Solar Panel Efficiency Forecasts with Innovative New Coating: Coating Provides 1.2 Percent Absolute Enhancement to Triple Junction Solar Cells December 2nd, 2016

Deep insights from surface reactions: Researchers use Stampede supercomputer to study new chemical sensing methods, desalination and bacterial energy production December 2nd, 2016

Spintronics

Making spintronic neurons sing in unison November 18th, 2016

Scientists find technique to improve carbon superlattices for quantum electronic devices: In a paradigm shift from conventional electronic devices, exploiting the quantum properties of superlattices holds the promise of developing new technologies October 20th, 2016

A new spin on superconductivity: Harvard physicists pass spin information through a superconductor October 16th, 2016

NREL discovery creates future opportunity in quantum computing: Research into perovskites looks beyond material's usage for efficient solar cells September 9th, 2016

Chip Technology

Construction of practical quantum computers radically simplified: Scientists invent ground-breaking new method that puts quantum computers within reach December 5th, 2016

Shape matters when light meets atom: Mapping the interaction of a single atom with a single photon may inform design of quantum devices December 4th, 2016

Quantum obstacle course changes material from superconductor to insulator December 1st, 2016

Bumpy surfaces, graphene beat the heat in devices: Rice University theory shows way to enhance heat sinks in future microelectronics November 29th, 2016

Memory Technology

New technology of ultrahigh density optical storage researched at Kazan University: The ever-growing demand for storage devices stimulates scientists to find new ways of improving the performance of existing technologies November 30th, 2016

A Tiny Machine: UCSB electrical and computer engineers design an infinitesimal computing device October 28th, 2016

How nanoscience will improve our health and lives in the coming years: Targeted medicine deliveries and increased energy efficiency are just two of many ways October 26th, 2016

Making the switch, this time with an insulator: Colorado State University physicists, joining the fundamental pursuit of using electron spins to store and manipulate information, have demonstrated a new approach to doing so, which could prove useful in the application of low-powe September 2nd, 2016

Discoveries

Construction of practical quantum computers radically simplified: Scientists invent ground-breaking new method that puts quantum computers within reach December 5th, 2016

Shape matters when light meets atom: Mapping the interaction of a single atom with a single photon may inform design of quantum devices December 4th, 2016

UTSA study describes new minimally invasive device to treat cancer and other illnesses: Medicine diffusion capsule could locally treat multiple ailments and diseases over several weeks December 3rd, 2016

Novel Electrode Structure Provides New Promise for Lithium-Sulfur Batteries December 3rd, 2016

Announcements

Construction of practical quantum computers radically simplified: Scientists invent ground-breaking new method that puts quantum computers within reach December 5th, 2016

Shape matters when light meets atom: Mapping the interaction of a single atom with a single photon may inform design of quantum devices December 4th, 2016

UTSA study describes new minimally invasive device to treat cancer and other illnesses: Medicine diffusion capsule could locally treat multiple ailments and diseases over several weeks December 3rd, 2016

Novel Electrode Structure Provides New Promise for Lithium-Sulfur Batteries December 3rd, 2016

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

Construction of practical quantum computers radically simplified: Scientists invent ground-breaking new method that puts quantum computers within reach December 5th, 2016

Shape matters when light meets atom: Mapping the interaction of a single atom with a single photon may inform design of quantum devices December 4th, 2016

UTSA study describes new minimally invasive device to treat cancer and other illnesses: Medicine diffusion capsule could locally treat multiple ailments and diseases over several weeks December 3rd, 2016

Deep insights from surface reactions: Researchers use Stampede supercomputer to study new chemical sensing methods, desalination and bacterial energy production December 2nd, 2016

Military

Quantum obstacle course changes material from superconductor to insulator December 1st, 2016

Physics, photosynthesis and solar cells: Researchers combine quantum physics and photosynthesis to make discovery that could lead to highly efficient, green solar cells November 30th, 2016

New method for analyzing crystal structure: Exotic materials called photonic crystals reveal their internal characteristics with new method November 30th, 2016

Inside tiny tubes, water turns solid when it should be boiling: MIT researchers discover astonishing behavior of water confined in carbon nanotubes November 30th, 2016

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