Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Non-volatile control of magnetic anisotropy through change of electric polarization

12.11.2019

Researchers from Kanazawa University use electrical polarization to control magnetic properties aiming for advanced memory applications

The ability to control the magnetic properties of a material using electricity is important for the development of computer technology, particularly nonvolatile memory, which is memory that requires no constant electrical supply to maintain a set state.


A schematic image of magnetic tunnel junction constructed of ferroelectric material sandwiched by magnetic metal layers. Interface of each electric polarization direction are shown enlarged in right-hand side. The diagram of electric resistance caused by electric polarization and magnetic directions are shown in bottom-left side.

Credit: Kanazawa University

That is, electrical control of the magnetic states of a material may allow us to realize the attractive energy-efficient concept of nonvolatile magnetic memory that is switched between different states using electricity.

Recently, Japanese researchers from Kanazawa University found that the magnetic properties of one metal layer could be controlled by applying electricity to an overlying metal oxide layer.

The research team investigated the change in the magnetic properties of a layer of cobalt-platinum alloy (CoPt) induced by the electrical polarization of an overlying zinc oxide (ZnO) layer.

Computational simulations showed that switching the electrical polarization of the ZnO layer had a large effect on the chemical potential at the interface between ZnO and CoPt, which in turn led to a considerable change in the magnetic behavior of the CoPt layer. The change of the magnetic behavior of the CoPt layer was nonvolatile; i.e., the layer remained in the set state until the electrical polarization of the ZnO layer was changed.

"The large effect of the electrical polarization of ZnO on the magnetic properties of CoPt could be explained by the polarization of ZnO providing control over the interactions of the atomic orbitals of CoPt," says author Masao Obata.

To confirm the promising results obtained from their simulations, the researchers fabricated a stacked structure called a tunnel junction containing Mg doped ZnO and CoPt layers. The magnetic properties and switching behavior of the tunnel junction were investigated.

The results revealed that the tunnel junction showed substantially different magnetic behavior depending on the electrical polarization state of the ZnO layer, providing qualitative agreement between the simulation results and theoretical findings.

"The ZnO/CoPt system demonstrates that it is possible to achieve nonvolatile electrical control of the magnetic properties of materials," explains co-author Tatsuki Oda. "Such a concept is important for the development of advanced energy-efficient nonvolatile magnetic memory."

The nonvolatile control of the magnetic behavior of CoPt by the electrical polarization of ZnO represents an attractive concept to realize new nonvolatile memory applications to further advance information processing.

Tomoya Sato | EurekAlert!
Further information:
https://doi.org/10.1103/PhysRevB.100.054423
http://dx.doi.org/10.1103/PhysRevB.100.054423

More articles from Physics and Astronomy:

nachricht Supporting structures of wind turbines contribute to wind farm blockage effect
13.12.2019 | American Institute of Physics

nachricht Chinese team makes nanoscopy breakthrough
13.12.2019 | Chinese Academy of Sciences Headquarters

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

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

Im Focus: Virus multiplication in 3D

Vaccinia viruses serve as a vaccine against human smallpox and as the basis of new cancer therapies. Two studies now provide fascinating insights into their unusual propagation strategy at the atomic level.

For viruses to multiply, they usually need the support of the cells they infect. In many cases, only in their host’s nucleus can they find the machines,...

Im Focus: Cheers! Maxwell's electromagnetism extended to smaller scales

More than one hundred and fifty years have passed since the publication of James Clerk Maxwell's "A Dynamical Theory of the Electromagnetic Field" (1865). What would our lives be without this publication?

It is difficult to imagine, as this treatise revolutionized our fundamental understanding of electric fields, magnetic fields, and light. The twenty original...

Im Focus: Highly charged ion paves the way towards new physics

In a joint experimental and theoretical work performed at the Heidelberg Max Planck Institute for Nuclear Physics, an international team of physicists detected for the first time an orbital crossing in the highly charged ion Pr⁹⁺. Optical spectra were recorded employing an electron beam ion trap and analysed with the aid of atomic structure calculations. A proposed nHz-wide transition has been identified and its energy was determined with high precision. Theory predicts a very high sensitivity to new physics and extremely low susceptibility to external perturbations for this “clock line” making it a unique candidate for proposed precision studies.

Laser spectroscopy of neutral atoms and singly charged ions has reached astonishing precision by merit of a chain of technological advances during the past...

Im Focus: Ultrafast stimulated emission microscopy of single nanocrystals in Science

The ability to investigate the dynamics of single particle at the nano-scale and femtosecond level remained an unfathomed dream for years. It was not until the dawn of the 21st century that nanotechnology and femtoscience gradually merged together and the first ultrafast microscopy of individual quantum dots (QDs) and molecules was accomplished.

Ultrafast microscopy studies entirely rely on detecting nanoparticles or single molecules with luminescence techniques, which require efficient emitters to...

Im Focus: How to induce magnetism in graphene

Graphene, a two-dimensional structure made of carbon, is a material with excellent mechanical, electronic and optical properties. However, it did not seem suitable for magnetic applications. Together with international partners, Empa researchers have now succeeded in synthesizing a unique nanographene predicted in the 1970s, which conclusively demonstrates that carbon in very specific forms has magnetic properties that could permit future spintronic applications. The results have just been published in the renowned journal Nature Nanotechnology.

Depending on the shape and orientation of their edges, graphene nanostructures (also known as nanographenes) can have very different properties – for example,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

The Future of Work

03.12.2019 | Event News

First International Conference on Agrophotovoltaics in August 2020

15.11.2019 | Event News

Laser Symposium on Electromobility in Aachen: trends for the mobility revolution

15.11.2019 | Event News

 
Latest News

Supporting structures of wind turbines contribute to wind farm blockage effect

13.12.2019 | Physics and Astronomy

Chinese team makes nanoscopy breakthrough

13.12.2019 | Physics and Astronomy

Tiny quantum sensors watch materials transform under pressure

13.12.2019 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>