I think of mechanical hard drives as "magnetic storage." I see no reason why this technology would benefit that.
SSD's currently use NAND flash which uses electrical transistors not magnetic storage. SSD-type devices (or RAM) are the only things that could benefit from something like this where it would somehow have to replace the flash chips currently being used in SSD's and RAM. Mechanical hard drives that currently use magnetic storage are limited by the speed of their moving parts, not the speed of polarity switching once the head passes over the write area. In order to benefit from this technology you would have to eliminate all moving parts (similar to SSD's)
Ultimately, it looks very underdeveloped, all that article says is that researchers were able to change the magnetic polarity of a few particles with heat. That's nowhere near being ready for the consumer market. Furthermore, where's the comparison to the polarity switching speed of currently used storage (aka using externally applied magnetic fields)? The only thing they really claim is energy savings (also not backed by any actual comparisons).
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