Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Computer models show device size matters

14.02.2014
Simulating the magnetic properties of nanostructures could help to design electronic memories with increased storage capacity

Scientists hope that patterning magnetic materials with nanometer-scale structures will help the development of non-volatile electronic memories with large storage capacities and no moving parts. So-called magnetoresistive random access memories are one example. But material properties at such tiny dimensions are not always the same as those of larger structures.


The ‘in-plane’ ferromagnetic-resonance response of a magnetic nanostructure changes with device size —shown here in the simulation results by the rapidly varying colors. The ‘out-of-plane’ response, on the other hand, is relatively constant.

© 2014 A*STAR Data Storage Institute

Kwaku Eason, Maria Sabino and their co-workers from the A*STAR Data Storage Institute, A*STAR National Metrology Centre and National University of Singapore have now modeled the changes in the characteristics of magnetic materials as devices are reduced in size to the nanoscale1.

The researchers focused their attention on modeling a powerful and widespread tool for characterizing magnetic materials called ferromagnetic resonance (FMR). FMR measures the absorption of microwave radiation by a thin sample. Knowing which microwave frequencies are absorbed the most can provide a number of key material properties. One such crucial property is the damping parameter, which is an indicator of how quickly a memory made from the magnetic material can store and release data.

The team employed a mathematical tool, known as the finite element method, to simulate a simple cylindrical nanodevice in all three dimensions. By calculating the energy levels of the device in an external magnetic field, the team could predict the FMR signal for devices of varying sizes.

The researchers compared their simulations to experimental data obtained on nanodisks made of a nickel–iron alloy, known as permalloy, and found good agreement for all device sizes. “Other groups have provided additional experimental results that further confirm the accuracy of our predictions,” says Eason.

The ability to predict the damping parameter of nanostructured magnetic materials is important because it is difficult to experimentally measure this property — partly because FMR signals from tiny targets are usually weak. Instead, researchers must study much larger devices and hope that the damping parameter is similar for nanostructures.

Recent experiments have conflicted on this point of scale. “One research group found from their experiments that device size does not matter in the damping measurement, while another group found that it does,” explains Eason. “We have resolved this dilemma: it turns out that they were both right.” Sabino adds: “The results were contradictory because of the different material properties.”

The simulations showed that the ‘in-plane’ magnetic properties are sensitive to the dimensions of the device, whereas the ‘out-of-plane’ properties are constant (see image).

“Contributing to a clear understanding of this effect is one of the most gratifying parts of this work,” says Eason.

The A*STAR-affiliated researchers contributing to this research are from the Singapore-based Data Storage Institute and the National Metrology Centre

Journal information

Eason, K., Sabino, M. P. R. G., Tran, M. & Liew, Y. F. Origins of magnetic damping measurement variations using ferromagnetic resonance for nano-sized devices. Applied Physics Letters 102, 232405 (2013).

A*STAR Research | Research asia research news
Further information:
http://www.a-star.edu.sg
http://www.researchsea.com
http://www.research.a-star.edu.sg/research/6881

More articles from Information Technology:

nachricht New technique controls autonomous vehicles on a dirt track
24.05.2016 | Georgia Institute of Technology

nachricht Engineers take first step toward flexible, wearable, tricorder-like device
24.05.2016 | University of California - San Diego

All articles from Information Technology >>>

The most recent press releases about innovation >>>

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

Im Focus: Computational high-throughput screening finds hard magnets containing less rare earth elements

Permanent magnets are very important for technologies of the future like electromobility and renewable energy, and rare earth elements (REE) are necessary for their manufacture. The Fraunhofer Institute for Mechanics of Materials IWM in Freiburg, Germany, has now succeeded in identifying promising approaches and materials for new permanent magnets through use of an in-house simulation process based on high-throughput screening (HTS). The team was able to improve magnetic properties this way and at the same time replaced REE with elements that are less expensive and readily available. The results were published in the online technical journal “Scientific Reports”.

The starting point for IWM researchers Wolfgang Körner, Georg Krugel, and Christian Elsässer was a neodymium-iron-nitrogen compound based on a type of...

Im Focus: Atomic precision: technologies for the next-but-one generation of microchips

In the Beyond EUV project, the Fraunhofer Institutes for Laser Technology ILT in Aachen and for Applied Optics and Precision Engineering IOF in Jena are developing key technologies for the manufacture of a new generation of microchips using EUV radiation at a wavelength of 6.7 nm. The resulting structures are barely thicker than single atoms, and they make it possible to produce extremely integrated circuits for such items as wearables or mind-controlled prosthetic limbs.

In 1965 Gordon Moore formulated the law that came to be named after him, which states that the complexity of integrated circuits doubles every one to two...

Im Focus: Researchers demonstrate size quantization of Dirac fermions in graphene

Characterization of high-quality material reveals important details relevant to next generation nanoelectronic devices

Quantum mechanics is the field of physics governing the behavior of things on atomic scales, where things work very differently from our everyday world.

Im Focus: Graphene: A quantum of current

When current comes in discrete packages: Viennese scientists unravel the quantum properties of the carbon material graphene

In 2010 the Nobel Prize in physics was awarded for the discovery of the exceptional material graphene, which consists of a single layer of carbon atoms...

Im Focus: Transparent - Flexible - Printable: Key technologies for tomorrow’s displays

The trend-forward world of display technology relies on innovative materials and novel approaches to steadily advance the visual experience, for example through higher pixel densities, better contrast, larger formats or user-friendler design. Fraunhofer ISC’s newly developed materials for optics and electronics now broaden the application potential of next generation displays. Learn about lower cost-effective wet-chemical printing procedures and the new materials at the Fraunhofer ISC booth # 1021 in North Hall D during the SID International Symposium on Information Display held from 22 to 27 May 2016 at San Francisco’s Moscone Center.

Economical processing

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Networking 4.0: International Laser Technology Congress AKL’16 Shows New Ways of Cooperations

24.05.2016 | Event News

Challenges of rural labor markets

20.05.2016 | Event News

International expert meeting “Health Business Connect” in France

19.05.2016 | Event News

 
Latest News

LZH shows the potential of the laser for industrial manufacturing at the LASYS 2016

25.05.2016 | Trade Fair News

Great apes communicate cooperatively

25.05.2016 | Life Sciences

Thermo-Optical Measuring method (TOM) could save several million tons of CO2 in coal-fired plants

25.05.2016 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>