Seagate has finally shipped their first 16TB HAMR disks for general data center use. The new HAMR technology has been under development for a very long time.
Now Seagate has developed it enough that concerns over the plates being damaged seem to be mitigated enough for general use. Hard disk plates are now mostly made of glass which can be made thinner than metal plates. The glass is coated with a magnetic material.
The laser is very low power as it focused very tightly. It used < 200mW which is small compared to the disk motor and logic board. The laser heats the material over its Curie temperature which lowers the coercivity so that it can be changed before the temperature is restored. Seagate has managed to focus the heat adequately to make it practical.
Seagate believes higher capacity disks will be available in a few years reaching perhaps 100TB in a 3½” disk. Such large capacities will possible as the superparamagnetic limit is not yet close to being an issue.
Early testing over the last 24 months has shown that the HAMR disks are working within expected values and performance. The move to volume production is expected to be sold to data centers who need more storage. The HAMR disks are also delivering over 20 times the expected transfer levels which is excellent news for consumers.
Consumer disks are available at up to 14TB which use the mature perpendicular recording technique. These disks are much less expensive.