Researchers find ferrimagnets could be used to speed up spintronics devices

September 25, 2018 by Bob Yirka, report
**Researchers find ferrimagnets could be used to speed up spintronics devices
Schematic of the Pt/Co44Gd56 layer structure in which ferrimagnetic Co44Gd56 exhibits a perpendicular magnetic anisotropy (the TaOx cap is not shown). Green (black) arrows indicate the Gd (Co) sublattice moments in a domain wall (DW) structure. Credit: Nature Nanotechnology (2018). DOI: 10.1038/s41565-018-0255-3

A team of researchers from MIT, the Max-Born-Institut, Technische Universität Berlin and Deutsches Elektronen-Synchrotron (DESY) has found that using ferrimagnets instead of ferromagnets could theoretically speed up spintronics devices. In their paper published in the journal Nature Nanotechnology, the group describes their research and what they found.

Spintronics devices make use of electron spin for a specific purpose. One possible application is in high-density storage devices. Such devices have been proposed using magnetic solitons (a type of quasiparticle) such as nanoscale in which a material has boundaries between areas where the point down on one side and up on the other, or magnetic skyrmions, which are particles related to baryons. In such a device, the solitons would serve as bits used to encode information—they would be moved using something called a racetrack, a device capable of moving domain walls or skyrmions along structures such as nanowires using current pulses that are spin-polarized. But to date, the development of a such a commercial device has been stymied by a problem—the bits are actually too big, which makes it difficult to move them fast enough to make the whole idea worthwhile. In this new effort, the research team suggests using ferrimagnets instead of using in such devices.

Ferromagnets are traditional magnets, materials that have properties that resemble iron. Ferrimagnets, on the other hand, are materials that have two types of ions with magnetic moments that are not equal, and which are also polarized in opposite directions. The researchers suggest using them could allow for the creation of smaller bits because they allow faster domain wall dynamics to occur—this is because there would be no change in net angular momentum required to reorient magnetic moments. They claim making the switch would allow for an order of magnitude improvement in both size and speed without resorting to cryogenics. This could result in the creation of new consumer products in a relatively short period of time.

Explore further: Bit data goes anti-skyrmions

More information: Lucas Caretta et al. Fast current-driven domain walls and small skyrmions in a compensated ferrimagnet, Nature Nanotechnology (2018). DOI: 10.1038/s41565-018-0255-3

Related Stories

Bit data goes anti-skyrmions

September 1, 2017

Today's world, rapidly changing because of "big data", is encapsulated in trillions of tiny magnetic objects - magnetic bits - each of which stores one bit of data in magnetic disk drives. A group of scientists from the Max ...

Magnetic vortices observed in haematite

August 13, 2018

Vortices are common in nature, but their formation can be hampered by long range forces. In work recently published in Nature Materials, an international team of researchers has used mapped X-ray magnetic linear and circular ...

Recommended for you

Graphene's magic is in the defects

December 18, 2018

A team of researchers at the New York University Tandon School of Engineering and NYU Center for Neural Science has solved a longstanding puzzle of how to build ultra-sensitive, ultra-small electrochemical sensors with homogenous ...

Carbon nanotubes mime biology

December 18, 2018

Cellular membranes serve as an ideal example of a system that is multifunctional, tunable, precise and efficient.

Deep learning democratizes nano-scale imaging

December 18, 2018

Many problems in physical and biological sciences as well as engineering rely on our ability to monitor objects or processes at nano-scale, and fluorescence microscopy has been used for decades as one of our most useful information ...

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

not rated yet Sep 25, 2018
Still 2 flux transversal's for magnetic particle / molecule to reorient giving a bit change boundary and 2D data storage. 3D (dimension) is the future, i.e. holographic.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.