If you haven’t already heard of antiferromagnetic spintronics it won’t be long before you do. This relatively unused class of magnetic materials could be about to transform our digital lives. They have the potential to make our devices smaller, faster, more robust and increase their energy efficiency.
Physicists at The University of Nottingham, working in collaboration with researchers in the Czech Republic, Germany and Poland, and Hitachi Europe, have published (14:00 EST Thursday January 14 2016) new research in the prestigious academic journal Science which shows how the ‘magnetic spins’ of these antiferromagnets can be controlled to make a completely different form of digital memory.
Lead researcher Dr Peter Wadley, from the School of Physics and Astronomy at The University of Nottingham, said: “This work demonstrates the first electrical current control of antiferromagnets. It utilises an entirely new physical phenomenon, and in doing so demonstrates the first all-antiferromagnetic memory device. This could be hugely significant as antiferromagnets have an intriguing set of properties, including a theoretical switching speed limit approximately 1000 times faster than the best current memory technologies.”
This entirely new form of memory has a set of properties which could make it extremely useful in modern electronics. It does not produce magnetic fields, meaning the individual elements can be packed more closely, leading to higher storage density. Antiferromagnet memory is also insensitive to magnetic fields and radiation making it particularly suitable for niche markets, such as satellite and aircraft electronics.
If all of this potential could be realised, antiferromagnetic memory would be an excellent candidate for a so-called “universal memory”, replacing all other forms of memory in computing, and transforming our electronic devices.
How did they do it?
Using a very specific crystal structure, CuMnAs, grown in almost complete vacuum, atomic layer by atomic layer — the research team has demonstrated that the alignment of the ‘magnetic moments’ of certain types of antiferromagnets can be controlled with electrical pulses through the material.
Dr Frank Freimuth of the Peter Grünberg Institute and the Institute for Advanced Simulation in Jülich said: “The electric current brings about a quantum mechanical torque on individual spins and allows each of them to tilt 90 degrees.” An effect first predicted by Dr Jakub Zelezny in Prague,Professor Tomas Jungwirth and colleagues at Nottingham.
What makes antiferromagnets better than ferromagnets?Ferromagnets react to external magnetic fields. For magnetic strips on credit cards or hard drives on computers, this effect is useful as it allows data to be written. But it is necessary to shield these materials from unwanted magnetic fields, generated for instance by certain kinds of medical equipment, so that data is not deleted by mistake.
Antiferromagnetic materials are not influenced by magnetic fields, and are of no use in magnetic data writing methods commonly utilised today. Until now, it has only been possible for them to be used in the field of information technology in combination with other classes of materials.
But antiferromagnets are magnetically more robust and can, in principle, be switched much faster than ferromagnets, so the research team decided to look for a way to develop them into an independent data storage material class.
As a result, they have succeeded in electrically controlling the switching and read-out of the magnetic moment of an antiferromagnetic material.
Dr Wadley said: “In contrast to current (ferromagnetic) memory technologies, our antiferromagnetic memory cannot be erased even by large magnetic fields. It also does not generate magnetic fields, meaning that the individual memory elements could be packed more closely together, leading to denser memory storage. Another foreseen advantage, which is yet to be established, is the speed by which information can be written in antiferromagnetic memories. Its physical limit is hundreds to thousands of times greater than in ferromagnets.
“The potential increase in speed of operation, robustness, energy efficiency and storage density could have a huge commercial and societal impact.”
The Latest on: Antiferromagnetic spintronics
via Google News
The Latest on: Antiferromagnetic spintronics
- Manipulating magnetic domain dynamics in ultrathin multi-layered materialson August 4, 2021 at 9:17 am
Spintronics is a branch of electronics that ... The research focuses on a device that combines so-called ferromagnetic and antiferromagnetic materials, in which the directions of electron spins ...
- A novel route to energy saving technologies in the IT sector: Controlling ferrimagnets by voltageon July 30, 2021 at 7:54 am
Geoffrey Beach from MIT, experts in hydrogen-based magneto-ionic devices and spintronics. Scheme of the optimized ... functionalized the GdCo/Pd/GdOx-layer structure with an additional ...
- Discovering energy saving technologies in the IT sector: Controlling ferrimagnets by voltageon July 29, 2021 at 5:00 pm
Geoffrey Beach from MIT, experts in hydrogen-based magneto-ionic devices and spintronics ... GdCo/Pd/GdOx-layer structure with an additional antiferromagnetic nickel oxide (NiO) layer.
- Graphene-mediated ferromagnetic coupling in the nickel nano-islands/graphene hybridon July 27, 2021 at 3:35 pm
The intrinsic ferromagnetism in graphene and antiferromagnetic exchange coupling between ... magnetic moments in applications such as quantum-based computation and spintronics. According to the ...
- Past Seminarson July 8, 2021 at 5:00 pm
Antiferromagnetic Spintronics with Topological Solitons Saitama, Japan Dec. 17, 2019 RIKEN Seminar: Multiple Zeta Values: Interrelation of Series and Integrals Saitama, Japan Dec. 17, 2019 RIKEN ...
- Scientists Provide Experimental Evidence for Zeeman Spin-Orbit Coupling in Antiferromagneticson April 22, 2021 at 5:06 am
Transfer from conventional electronics to spintronics technology opens the possibilities to construct devices with high storage density and fast operation. The two-component nature of spin ...
- Spintronics: the dance of the unpaired electronson August 28, 2019 at 12:36 am
Dancing electrons Image: Dmytro Kysylychyn, Qmag Physicists and material scientists nowadays research on many different directions of spintronics, like for example antiferromagnetic spintronics.
via Bing News