Batman lights the way to compact data storage
Researchers at PSI spotted a curious black-and-white magnetic substructure on a five-by-five micrometre square – and were reminded of the stylised Batman logo. The black areas reveal where the magnetisation is pointing downwards, i.e. into the picture; the white ones where it is pointing upwards.
© PSI
Researchers at the Paul Scherrer Institute (PSI) have succeeded in switching tiny, magnetic structures using laser light and tracking the change over time. In the process, a nanometre-sized area bizarrely reminiscent of the Batman logo appeared. The research results could render data storage on hard drives faster, more compact and more efficient.
Excerpt of the PSI-Press release:
The researchers at PSI teamed up with colleagues from the Netherlands, Germany and Japan for the project. Two years ago, the international research team already succeeded in demonstrating that a short, intensive laser pulse can switch micro-magnets hundreds of times faster than a magnetic head. And the laser is lower in energy and thus more cost-effective, too. The trick evidently lies in the fact that the laser light heats up the tiny magnets very quickly and is thus able to convert them into the other state. “Using light for magnetic switching clearly works. But why exactly it does is still the subject of debate in the research community,” explains Frithjof Nolting, the lab head on the PSI study.
“This could be the way to store even more data on even smaller hard drives one day,” says Loïc Le Guyader, who was also involved in the PSI experiments, and is now working at the Helmholtz-Zentrum Berlin.
Please read the complete press release here:
http://www.psi.ch/media/batman-lights-the-way-to-compact-data-storage
Publication: Nanoscale sub-100 picosecond all-optical magnetization switching in GdFeCo microstructures.
L. Le Guyader, M. Savoini, S. El Moussaoui, M. Buzzi, A. Tsukamoto, A. Itoh, A. Kirilyuk, T. Rasing, A.V. Kimel and F. Nolting,
Nature Communications, 12 January 2014,
DOI: 10.1038/ncomms6839
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