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Primeur weekly 2013-01-21

The Cloud

HP helps service provider ITX Enterprises expand private Cloud service delivery ...

IBM and the Australian Open mark 20 years of serving a winning advantage to tennis fans ...

Ho Chi Minh City University of Information Technology selects IBM PureSystems ...

Oracle delivers Oracle Infrastructure as a Service on Premise with Capacity on Demand ...

Clouds for Savings, Clouds for Quality - Governments leading by example at Cloudscape V ...

EuroFlash

German meteorological service DWD awards $23 million contract to Cray ...

Adaptive Computing to work with Cray to manage computing workloads for the North-German Supercomputing Alliance (HLRN) ...

PRACE Summer of HPC ...

Altair's HyperWorks Partner Alliance expands its scope with the addition of NovaCast Systems to its software line-up ...

Altair releases PBS Professional 12.0, with 40 percent faster scheduling, innovative utilization features and additional plug-ins for execution events ...

Computational methods reveal how hospital-acquired bacteria spread ...

A new dimension in mobile telecommunications ...

Sauber F1 Team fuels chase for podium finishes with NetApp storage foundation ...

Mathematical breakthrough sets out rules for more effective teleportation ...

Bright Cluster Manager speeds Chinese climate change research efforts ...

USFlash

Asia Student Supercomputer Challenge 2013 to issue Call for Participation ...

Chaotic spin vortices could lead to new computer memories ...

2013 IEEE International Conference on Big Data to issue Call for Workshop Proposals ...

Intel and Facebook collaborate on future data centre rack technologies ...

UC Riverside nanotechnologists help launch new national centre devoted to micro-electronics ...

NETL's new supercomputer ranks among the world's Top 100 ...

Notre Dame to be part of $194 million university research centre network ...

Coles Supermarkets revamps data warehouse system with Oracle ...

FAIR Health selects Oracle Exadata Database Machine and Oracle's Sun ZFS storage appliance ...

Oracle's consolidated data warehouse system helps Turkcell accelerate reporting, and save on storage and energy costs ...

Simon Fraser University materials and particle science attract government funding ...

Researchers at Mount Sinai School of Medicine use TACC supercomputers to simulate the organisation of membrane proteins at the cell surface ...

Chaotic spin vortices could lead to new computer memories

2 Jan 2013 Argonne - In science, just like in life, sometimes creating the most effective organisation depends on being able to handle just a bit of chaos first. Scientists at the U.S. Department of Energy's Argonne National Laboratory have used alternating magnetic fields to control the behaviour of "spin vortices" trapped in small dots made from iron and nickel that can be magnetized in two separate ways. While the majority of these structures are magnetized in-plane either clockwise or counter-clockwise, a tiny region at their centres - the vortex core - is magnetized out of plane, either up or down.

"If you were able to visualize it, it would look like a funnel", stated Argonne materials scientist Valentyn Novosad.

Valentyn Novosad and postdoctoral researcher Shikha Jain wanted to find a way to control the magnetic states of pairs or even large groups of these dots that interacted with each other in a lattice.

In the resting state, the cores of the dots are randomly polarized. After applying an oscillating magnetic field to the pairs of dots, the researchers observed that the central cores began to switch back and forth repeatedly between up- and down-magnetizations - which Shikha Jain and Valentyn Novosad characterized as "chaos".

This chaotic system's behaviour is dictated by the fact that the magnetic field, when applied, oscillates at a particular frequency that can be tuned to match the "resonance frequency" - that is, the natural frequency of vibration - for a specific polarity combination in a dot-pair. Each pair of dots has two resonance frequencies, corresponding to parallel (up-up or down-down) or antiparallel (up-down or down-up) magnetization states. In the parallel state, the dots' centres are magnetized in the same direction, while in the antiparallel state they are opposite.

By increasing and then decreasing the strength of the applied field, Argonne's scientists were able to bring the dots' magnetizations into and then out of chaos. When the amplitude of the oscillating field was reduced significantly, the researchers discovered that the new polarizations corresponded to the opposite state of the applied frequency. If the frequency corresponded to the parallel magnetization, an antiparallel arrangement would emerge, and vice versa.

"We were somewhat surprised that the behaviours of multiple dots could be controlled so precisely", Shikha Jain stated. "There had been a lot of work done before on single-dot systems, but no one had really investigated how magnetic dots interact with each other in this kind of environment."

By achieving consistent control of the central polarization's direction, the researchers moved one step closer to creating new magnetic devices, including non-volatile random access memories. These devices are the subject of intense research in academia and industry worldwide as they offer energy efficiency, high operating speed and exceptional reliability. Unlike the silicon-based chips in today's computers, their magnetic counterparts employ spin rather than electric charge to store and process information.

According to Valentyn Novosad, the underlying physics that governs the two-dot interaction should apply as well to a system of many elements. Future studies will seek to explore the collective dynamics in larger three-dimensional crystal-like magnetic structures.

These results were published in the journalNature Communications. The paper is titled "From chaos to selective ordering of vortex cores in interacting mesomagnets". Shikha Jain is a lead author and Valentyn Novosad is the corresponding author of the paper. Co-authoring this paper were Argonne's Distinguished Fellows Frank Fradin and Samuel Bader, senior materials engineer John Pearson, and professors Andrei Slavin and Vasyl Tiberkevich from Oakland University in Rochester, Michigan.
Source: Argonne National Laboratory

Back to Table of contents

Primeur weekly 2013-01-21

The Cloud

HP helps service provider ITX Enterprises expand private Cloud service delivery ...

IBM and the Australian Open mark 20 years of serving a winning advantage to tennis fans ...

Ho Chi Minh City University of Information Technology selects IBM PureSystems ...

Oracle delivers Oracle Infrastructure as a Service on Premise with Capacity on Demand ...

Clouds for Savings, Clouds for Quality - Governments leading by example at Cloudscape V ...

EuroFlash

German meteorological service DWD awards $23 million contract to Cray ...

Adaptive Computing to work with Cray to manage computing workloads for the North-German Supercomputing Alliance (HLRN) ...

PRACE Summer of HPC ...

Altair's HyperWorks Partner Alliance expands its scope with the addition of NovaCast Systems to its software line-up ...

Altair releases PBS Professional 12.0, with 40 percent faster scheduling, innovative utilization features and additional plug-ins for execution events ...

Computational methods reveal how hospital-acquired bacteria spread ...

A new dimension in mobile telecommunications ...

Sauber F1 Team fuels chase for podium finishes with NetApp storage foundation ...

Mathematical breakthrough sets out rules for more effective teleportation ...

Bright Cluster Manager speeds Chinese climate change research efforts ...

USFlash

Asia Student Supercomputer Challenge 2013 to issue Call for Participation ...

Chaotic spin vortices could lead to new computer memories ...

2013 IEEE International Conference on Big Data to issue Call for Workshop Proposals ...

Intel and Facebook collaborate on future data centre rack technologies ...

UC Riverside nanotechnologists help launch new national centre devoted to micro-electronics ...

NETL's new supercomputer ranks among the world's Top 100 ...

Notre Dame to be part of $194 million university research centre network ...

Coles Supermarkets revamps data warehouse system with Oracle ...

FAIR Health selects Oracle Exadata Database Machine and Oracle's Sun ZFS storage appliance ...

Oracle's consolidated data warehouse system helps Turkcell accelerate reporting, and save on storage and energy costs ...

Simon Fraser University materials and particle science attract government funding ...

Researchers at Mount Sinai School of Medicine use TACC supercomputers to simulate the organisation of membrane proteins at the cell surface ...