Subscribe to our free daily newsletters
. 24/7 Space News .




Subscribe to our free daily newsletters



CHIP TECH
Spin current on topological insulator detected at room temps
by Staff Writers
Goteborg, Sweden (SPX) Dec 12, 2015


This image shows the schematics of the spin current on a topological insulator surface, with the spin direction (S) perpendicular to the current direction (kx). The zoom in schematic shows the electronic band structure on the surface of the topological insulator. The spin polarization on topological insulator surface is electrically probed by a ferromagnetic tunnel contact (FM). Image courtesy Andre Dankert. For a larger version of this image please go here.

Researchers at Chalmers University of Technology have for the first time reported the electrical detection of spin current on topological insulator surfaces at room temperature by employing a ferromagnetic detector. The findings have been published in the journal Nano Letters.

Solid-state materials were conventionally divided into three different classes such as conductors, semiconductors and insulators. Recently, a new class of materials has been proposed and realized, called "topological insulators", where both the insulating and conducting properties can co-exist in the same material.

Topological insulators are insulators inside the bulk, but are conducting on their surfaces with less resistance than the conventional materials. This is possible due to their uniquely strong interaction between electrons' spin and orbital angular momentum with their time reversal symmetry. The interaction is so strong that the spin angular momentum of the electrons is locked perpendicular to their momentum, and generates a spontaneous spin polarized current on the surfaces of topological insulators by applying an electric field.

These spin polarized conducting electrons on the surface have no mass and are extremely robust against most perturbations from defects or impurities, and can enable the propagation of dissipationless spin currents.

The researchers from Chalmers detected the surface spin current electrically on a topological insulator called bismuth selenide (Bi2Se3) for the first time at room temperature employing ferromagnetic tunnel contacts. Such contacts are known to be very sensitive to spin polarization and probe the Bi2Se3 surface by measuring the magnetoresistance due to parallel and anti-parallel alignment of the spin current and the ferromagnet magnetization direction.

"The key factors for these room temperature results are good quality topological insulator crystals and spin sensitive ferromagnetic tunnel contacts carefully prepared by clean room nanofabrication", explains Dr. Andre Dankert, the lead author of the paper.

Earlier reports in this research field were limited only to measurements at cryogenic temperatures. From the results on the magnitude of the spin signal, its sign, and control experiments, using different measurement configurations, angles and interface conditions, the author's rule out other known physical effects.

"Our results show the electrical accessibility of spin currents on topological insulator surfaces up to room temperature and pave the way for further developments, which can be useful for spin based information processing in the future", says associate professor Saroj Dash, who leads the research group.

However, Saroj Dash cautions that the research on development of these new class materials and measurement techniques are still in its early stage and more experiments are required for further understanding.

Article "Room Temperature Electrical Detection of Spin Polarized Currents in Topological Insulators"

Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.

SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only

.


Related Links
Chalmers University of Technology
Computer Chip Architecture, Technology and Manufacture
Nano Technology News From SpaceMart.com






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

Previous Report
CHIP TECH
Quantum computer made of standard semiconductor materials
Munich, Germany (SPX) Dec 09, 2015
Physicists at the Technical University of Munich, the Los Alamos National Laboratory and Stanford University (USA) have tracked down semiconductor nanostructure mechanisms that can result in the loss of stored information - and halted the amnesia using an external magnetic field. The new nanostructures comprise common semiconductor materials compatible with standard manufacturing processes. ... read more


CHIP TECH
Gaia's sensors scan a lunar transit

SwRI scientists explain why moon rocks contain fewer volatiles than Earth's

All-female Russian crew starts Moon mission test

Russian moon mission would need 4 Angara-A5V launches

CHIP TECH
Mars Mission Team Addressing Vacuum Leak on Key Science Instrument

Letter to Mars? Royal Mail works it out for British boy, 5

European payload selected for ExoMars 2018 surface platform

ExoMars has historical, practical significance for Russia, Europe

CHIP TECH
Australia seeks 'ideas boom' with tax breaks, visa boosts

Orion's power system to be put to the test

The Ins and Outs of NASA's First Launch of SLS and Orion

Aerojet Rocketdyne tapped for spacecraft's crew module propulsion

CHIP TECH
China's indigenous SatNav performing well after tests

China launches Yaogan-29 remote sensing satellite

China's scientific satellites to enter uncharted territory

China to launch Dark Matter Satellite in mid-December

CHIP TECH
Getting Into the Flow on the ISS

Orbital to fly first space cargo mission since 2014 explosion

Russian-US Space Collaboration Intact Despite Chill in Bilateral Ties

ISS EarthKAM ready for student imaging request

CHIP TECH
Orbital cargo ship blasts off toward space station

Virgin Galactic Welcomes 'Cosmic Girl' To Fleet Of Space Access Vehicles

DXL-2: Studying X-ray emissions in space

Arianespace selected to launch Azerspace-2/Intelsat 38 satellites

CHIP TECH
What kinds of stars form rocky planets

Half of Kepler's giant exoplanet candidates are false positives

Exiled exoplanet likely kicked out of star's neighborhood

Neptune-size exoplanet around a red dwarf star

CHIP TECH
Penn researchers make thinnest plates that can be picked up by hand

World's tiniest temperature sensor can track movement from inside cement

Researchers discover mother of pearl production process

In-Space Manufacturing Prototype




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News






The content herein, unless otherwise known to be public domain, are Copyright 1995-2017 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement