this whole concept makes me nervous. also:

It should be noted that while the method is possible in the lab, it looks rather costly as it requires significantly different read/write heads and more complex platters with two (or more) layers of granular magnetic layers. Granular media, ordered granular media, and then bit patterned media promise to increase the areal density of HDD disks without such extreme complexities, so it is hard to imagine dual-layer and multi-layer media being used in the near future. Yet, once the industry gets to bit patterned media, it might look back and reconsider multi-layer media as a means to increase recording density and HDD capacity.

boo

I worked in data storage for a couple of years, and HAMR was just starting to be a thing when I left. So cool to see how far it has come.