Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A new magnetoresistance effect occurring in materials with strong spin-orbit coupling

27.01.2016

These materials, which include metals such as platinum or tantalum, are characterized for being capable of generating a spin current from an electrical current (and viceversa) by means of the so-called spin Hall effect. For this reason, these materials are of outmost importance in the field of spintronics -the branch of science that is devoted to explore the generation, transmission and detection of spin currents in materials and devices.

The ultimate goal of spintronics is to have a deeper understanding of the charge-to-spin conversion and transport phenomena at the nanoscale in order to be able to design new functional and efficient devices that are not only based on the injection, transport and storage of electrical charge, but also to its spin, which could revolutionize the conventional electronics and expand its limits.


Top: Schematic of the direct spin Hall effect (and its inverse) in a thin film of a material with strong spin-orbit coupling. Bottom: schematic of the Hanle magnetoresistance effect when an external magnetic field is applied.

Credit: PR

The researchers show that, by means of this novel magnetoresistive effect, it is now possible to study the spin transport properties in these materials without the need to fabricate complex devices and/or involve interfaces between different materials.

When an electric current is applied to a thin film of a material with strong spin-orbit coupling (typically of a few nanometers thick), a spin current is generated in the transverse direction -that is, along the thickness of the film- via the direct spin Hall effect, which in turn produces an electric current (via the inverse spin Hall effect) that adds to the initial applied current.

This effect -small since it is due to a second-order correction-, causes a reduction in the resistivity of the film, and is maximum when the film thickness is on the order of to the spin diffusion length -that is, the average distance that a spin can travel through the material without suffering a collision that may cause a change in its state.

If a magnetic field is applied not collinear to the direction where the spins points to, one can force them to precess -via the so-called Hanle effect-, thereby generating a modulation in the resistivity of the material. According to Saul Velez, first author of the work, "this new phenomenon could open ahead the possibility to study the spin transport in materials and systems not yet explored".

"This new effect also allows to study the spin transport properties of known materials, and to compare the results with the ones obtained with other techniques or devices", adds Fèlix Casanova, last author and supervisor of the work.

Media Contact

Irati Kortabitarte
i.kortabitarte@elhuyar.com
34-943-363-040

Irati Kortabitarte | EurekAlert!

More articles from Materials Sciences:

nachricht ADIR Project: Lasers Recover Valuable Materials
21.07.2017 | Fraunhofer-Institut für Lasertechnik ILT

nachricht High-tech sensing illuminates concrete stress testing
20.07.2017 | University of Leeds

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

Im Focus: The proton precisely weighted

What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.

To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...

Im Focus: On the way to a biological alternative

A bacterial enzyme enables reactions that open up alternatives to key industrial chemical processes

The research team of Prof. Dr. Oliver Einsle at the University of Freiburg's Institute of Biochemistry has long been exploring the functioning of nitrogenase....

Im Focus: The 1 trillion tonne iceberg

Larsen C Ice Shelf rift finally breaks through

A one trillion tonne iceberg - one of the biggest ever recorded -- has calved away from the Larsen C Ice Shelf in Antarctica, after a rift in the ice,...

Im Focus: Laser-cooled ions contribute to better understanding of friction

Physics supports biology: Researchers from PTB have developed a model system to investigate friction phenomena with atomic precision

Friction: what you want from car brakes, otherwise rather a nuisance. In any case, it is useful to know as precisely as possible how friction phenomena arise –...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

The technology with a feel for feelings

12.07.2017 | Event News

 
Latest News

NASA looks to solar eclipse to help understand Earth's energy system

21.07.2017 | Earth Sciences

Stanford researchers develop a new type of soft, growing robot

21.07.2017 | Power and Electrical Engineering

Vortex photons from electrons in circular motion

21.07.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>