Not too long ago, when a company claimed it would double the size of hard drive capacity, we thought it was ridiculous. Things have changed and as technology and the way data is stored improves, drive capacity is rapidly expanding. 12TB drives are available to consumers for a very low price per GB of storage. In these new drives, microwaves will be used to write data onto drives making the actual physical unit of data smaller - while storing the same amount of data in that block. Super cool stuff that will probably require helium at the very least to keep it cool. Good luck trying to get your data back when a drive fails.
An allied method that uses heat instead of microwaves was thought to be the best way to help HDDs grow in capacity but it is known to be an expensive and technically tricky way to boost data density. The resulting devices, whose platters must be regularly heated beyond 400C, can also suffer reliability problems. Heat-assisted magnetic recording also requires changes in manufacturing plants and the materials used to make the magnetic platters that hold data. By contrast, MAMR requires far fewer changes to manufacturing and works with materials currently used to make HDDs.
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