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Primeur weekly 2017-02-06

Focus

Photon and Neutron Community ready to act as a go-between for the e-Infrastructures and user communities ...

Bridging socio-cultural distance in science through technical community-engaging mechanisms ...

Exascale supercomputing

How to improve data management in the supercomputers of the future ...

Crowd computing

Your computer can help scientists search for new childhood cancer treatments ...

Quantum computing

Quantum phase transition observed for the first time ...

Quantum matter: Shaken, but not stirred ...

First ever blueprint unveiled to construct a large scale quantum computer ...

Focus on Europe

PRACE opens Tier-1 for Tier-0 service ...

Middleware

New version of Univa Unisight 4.1 provides comprehensive tool to support IT purchasing decisions ...

Czech TV speeds broadcast and production delivery with DDN's fully integrated MEDIAScaler platform ...

Optimized compiler yields more-efficient parallel programmes ...

Hardware

Three magnetic states for each hole: researchers investigate the potential of metal grids for electronic components ...

Making the switch to polarization diversity ...

SDSC's 'Comet' supercomputer surpasses '10,000 users' milestone ...

New Cheyenne supercomputer triples scientific capability with greater efficiency ...

GBP 3.2 million for Midlands-based high performance computing centre ...

Applications

Machine learning accurately predicts metallic defects ...

Jupiter Medical Center implements revolutionary Watson for Oncology to help oncologists make data-driven cancer treatment decisions ...

University of Delaware's Anderson Janotti receives NSF Career Award to model defects in complex materials ...

Supercomputing and experiment combine for first look at magnetism of real nanoparticle ...

Researchers flip script for Li-Ion electrolytes to simulate better batteries ...

Huawei and SURFsara join forces for ICT innovation in Smart Healthcare and Smart Energy ...

The shape of melting in two dimensions: University of Michigan team uses Titan to explore fundamental phase transitions ...

Nature Geoscience highlights CALIOPE's ability to "provide decision makers with the information they need to take preventive action" on air quality ...

Magnetic recording with light and no heat on garnet ...

Breaking the jargon barrier ...

Carnegie Mellon Artificial Intelligence beats top poker pros ...

Preventing blood clots with a new metric for heart function: Simulations on Stampede supercomputer reveal better way of predicting future clots in the left ventricle ...

Berkeley Lab resources used to model superluminous supernova in 2D for first time ...

The Cloud

Utilities regulators see value in the Cloud and Cloud technology investments as critical to utilities' success ...

Magnetic recording with light and no heat on garnet


Cobalt garnet is a glassy, transparent material. The researchers use small pieces for their experiments.
18 Jan 2017 Nijmegen - A strong short light pulse can record data on a magnetic layer of yttrium iron garnet doped with Co-ions. This was discovered by researchers from Radboud University in The Netherlands and Bialystok University in Poland. The novel mechanism outperforms existing alternatives allowing ever fastest write-read magnetic recording accompanied by unprecedentedly low heat load, the scientific magazineNaturereported on January 18 2017.

Reliable, cheap and quick data recording will be as crucial to 21st century economics as oil was to that of the 20th century. Magnetic recording performs rather well in that respect, but data centres are getting overheated due to the sharp rise in demand of Cloud storage - think of all our Facebook and WhatsApp traffic. A lot of energy is needed to cool their processors. Heat Assisted Magnetic Recording or HAMR, the latest innovation in magnetic recording, will not solve this problem. On the contrary: it uses the heat of a laser pulse to speed up the recording process. For this reason, super-fast magnetic recording that produces no heat and does not need electromagnets is the holy grail of current fundamental and applied research on magnetism.

Researchers from Radboud University have been experimenting with ways to use the energy of a light pulse to manipulate magnets for more than a decade. Professor Theo Rasing and his colleagues published their first results in a 2007 article in the international journalScience.

The problem with their initial findings was that the mechanism of the recording relied on laser-induced heating that reached temperatures close to the so called Curie temperature, above which the magnetic order is destroyed. The recording via heating and partial destruction of the magnetic order seriously hampered potential applications. Heating negatively affects thermal stability of a recording medium, limits the repetition frequency by the cooling time, and limits the recording density due to heat diffusion.

In order to tackle the heating problem, one would need a medium with low optical absorption. For metals with a lot of free electrons, the absorption of light - and thus heating of the material - is unavoidable. It means that in order to reduce the heating, a dielectric material needs to be used. For this study the scientists chose yttrium iron garnet (YIG) - one of the model magnetic dielectrics in fundamental and applied research. It is impossible to record information through light on normal YIG. But to increase its sensitivity to optical excitation, the scientists doped it with Co-ions.

Co-ions are known for the strong coupling of magnetic moments to the orbital motion of electron - so-called spin-orbit interaction. Light can effectively change orbital motion of the electrons in the ions and thus affect magnetism. Experiments fully met the expectations of the scientists. They found that in the Co-substituted garnet film, a single linearly polarized femtosecond laser pulse promotes switching of spins between different states.

"By changing the polarization of the laser pulse we deterministically steer the net magnetization in the garnet: we write 0 and 1 magnetic bits at will", physicist Alexey Kimel from Radboud University explained. "This mechanism outperforms existing alternatives, allowing the fastest ever magnetic write-read recording event, lower than twenty pico-seconds, accompanied by unprecedentedly low heat load." Alexey Kimel had trouble getting funding for this project because his idea was considered too exotic to possibly be true. The publication inNatureproves that he was right from the start.

Using light for magnetic switching on garnet films will probably not be applied in personal computers. "The technology gap between storing on metal and garnet crystal is too big", Alexey Kimel thinks. "But it could be an interesting option for the Big Data warehouses of Google and Facebook and the like. Another possible use could be data recording at very low temperatures. Superconducting electronics and quantum computers lack a fast memory system that can record at temperatures below 10 Kelvin (-263 degrees Celsius). Up until now this was a serious obstacle for superconducting computing."

The paper titled " Ultrafast nonthermal photo-magnetic recording in transparent medium " is authored by A. Stupakiewicz, K. Szerenos, D. Afanasiev, A. Kirilyuk & A.V. Kimel. It is published inNature- doi:10.1038/nature20807.
Source: Radboud University

Back to Table of contents

Primeur weekly 2017-02-06

Focus

Photon and Neutron Community ready to act as a go-between for the e-Infrastructures and user communities ...

Bridging socio-cultural distance in science through technical community-engaging mechanisms ...

Exascale supercomputing

How to improve data management in the supercomputers of the future ...

Crowd computing

Your computer can help scientists search for new childhood cancer treatments ...

Quantum computing

Quantum phase transition observed for the first time ...

Quantum matter: Shaken, but not stirred ...

First ever blueprint unveiled to construct a large scale quantum computer ...

Focus on Europe

PRACE opens Tier-1 for Tier-0 service ...

Middleware

New version of Univa Unisight 4.1 provides comprehensive tool to support IT purchasing decisions ...

Czech TV speeds broadcast and production delivery with DDN's fully integrated MEDIAScaler platform ...

Optimized compiler yields more-efficient parallel programmes ...

Hardware

Three magnetic states for each hole: researchers investigate the potential of metal grids for electronic components ...

Making the switch to polarization diversity ...

SDSC's 'Comet' supercomputer surpasses '10,000 users' milestone ...

New Cheyenne supercomputer triples scientific capability with greater efficiency ...

GBP 3.2 million for Midlands-based high performance computing centre ...

Applications

Machine learning accurately predicts metallic defects ...

Jupiter Medical Center implements revolutionary Watson for Oncology to help oncologists make data-driven cancer treatment decisions ...

University of Delaware's Anderson Janotti receives NSF Career Award to model defects in complex materials ...

Supercomputing and experiment combine for first look at magnetism of real nanoparticle ...

Researchers flip script for Li-Ion electrolytes to simulate better batteries ...

Huawei and SURFsara join forces for ICT innovation in Smart Healthcare and Smart Energy ...

The shape of melting in two dimensions: University of Michigan team uses Titan to explore fundamental phase transitions ...

Nature Geoscience highlights CALIOPE's ability to "provide decision makers with the information they need to take preventive action" on air quality ...

Magnetic recording with light and no heat on garnet ...

Breaking the jargon barrier ...

Carnegie Mellon Artificial Intelligence beats top poker pros ...

Preventing blood clots with a new metric for heart function: Simulations on Stampede supercomputer reveal better way of predicting future clots in the left ventricle ...

Berkeley Lab resources used to model superluminous supernova in 2D for first time ...

The Cloud

Utilities regulators see value in the Cloud and Cloud technology investments as critical to utilities' success ...