Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Magnetic materials: Forging ahead with a back-to-basics approach

30.08.2013
Atomic-level simulations hint at how to control the magnetic properties of layered materials for data storage applications

Scientists have recently started to explore the possibility of using an intrinsic property of the electron known as spin for processing and storing information. Magnetic fields can influence the dynamics of electron spin, so harnessing this potential relies on precision engineering of crystalline storage materials.


The atoms in a crystalline material known as Co4Pd1 are arranged into stacked layers labeled A, B and C (left). A single ‘mistake’ in this arrangement (right) can affect the material’s properties.

Modified, with permission, from Ref. 1 © 2012 EPLA

Chee Kwan Gan and co©workers at the A*STAR Institute of High Performance Computing and the A*STAR Data Storage Institute in Singapore have used theoretical calculations to show how the magnetic characteristics of specific materials can be controlled at the atomic level1. Their results could lead to novel magnetic recording devices.

One promising route to such spintronic devices is to design structures consisting of alternating layers of different magnetic atoms. The strength of the magnetic influence is stronger in the direction of the multilayer stack than it is parallel to the planes of the atoms. This so-called perpendicular magnetic anisotropy is useful for spintronic memory devices because it allows a greater storage density than a conventional electronic device.

The properties of these structures, however, are highly sensitive to the precise arrangement of the crystal. Just one misplaced layer of atoms ¡ª a stacking fault ¡ª can noticeably alter device performance (see image). Previous studies usually ignored these special defects, ¡°but nature sometimes makes ¡®mistakes¡¯,¡± explains Gan. ¡°It is important to understand these defects and subsequently use them to control the material¡¯s physical properties.¡±

Gan and his team went back to basics to better understand how atom-level imperfections affect the properties of these multilayers. They used a powerful mathematical approach known as density functional theory. This approach uses only fundamental equations from quantum mechanics to model the behavior of electrons in these structures, without requiring any prior assumptions.

The researchers modeled a material consisting of alternating layers of cobalt and palladium atoms. Multilayers of these atoms have previously exhibited a large perpendicular magnetic anisotropy when the cobalt layers are less than 0.8 nanometers thick. Gan and co-workers then assessed how stacking faults and the ratio of cobalt to palladium atoms affected this anisotropy. Their results showed that a stacking fault could enhance the magnetic anisotropy in structures with a relatively thick cobalt layer. They also found that the anisotropy increased almost linearly with increasing cobalt content.

High magnetic anisotropy materials have potential for use in the next generation of ultrafast and high-capacity magnetic random-access memory, Gan explains. The improved understanding of these materials from this research will guide the way to realizing such devices.

The A*STAR-affiliated researchers contributing to this research are from the Institute of High Performance Computing and the Data Storage Institute

Journal information

Wu, G., Khoo, K. H., Jhon, M. H., Meng, H., Lua, S. Y. H. et al. First-principles calculations of the magnetic anisotropic constants of Co¨CPd multilayers: Effect of stacking faults. Europhysics Letters 99, 17001 (2012).

A*STAR Research | Research asia research news
Further information:
http://www.research.a-star.edu.sg/research/6727
http://www.researchsea.com

More articles from Materials Sciences:

nachricht Scientists create innovative new 'green' concrete using graphene
24.04.2018 | University of Exeter

nachricht Neutrons provide insights into increased performance for hybrid perovskite solar cells
24.04.2018 | DOE/Oak Ridge National Laboratory

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: BAM@Hannover Messe: innovative 3D printing method for space flight

At the Hannover Messe 2018, the Bundesanstalt für Materialforschung und-prüfung (BAM) will show how, in the future, astronauts could produce their own tools or spare parts in zero gravity using 3D printing. This will reduce, weight and transport costs for space missions. Visitors can experience the innovative additive manufacturing process live at the fair.

Powder-based additive manufacturing in zero gravity is the name of the project in which a component is produced by applying metallic powder layers and then...

Im Focus: Molecules Brilliantly Illuminated

Physicists at the Laboratory for Attosecond Physics, which is jointly run by Ludwig-Maximilians-Universität and the Max Planck Institute of Quantum Optics, have developed a high-power laser system that generates ultrashort pulses of light covering a large share of the mid-infrared spectrum. The researchers envisage a wide range of applications for the technology – in the early diagnosis of cancer, for instance.

Molecules are the building blocks of life. Like all other organisms, we are made of them. They control our biorhythm, and they can also reflect our state of...

Im Focus: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

Im Focus: Gamma-ray flashes from plasma filaments

Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.

The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Quantum Technology for Advanced Imaging – QUILT

24.04.2018 | Information Technology

AWI researchers measure a record concentration of microplastic in arctic sea ice

24.04.2018 | Earth Sciences

Complete skin regeneration system of fish unraveled

24.04.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>