I worked in this area of magnetics, and it’s been in research for at least 15 years. Companies had made devices by about 10 years ago but the storage capacities

I worked in this area of magnetics, and it’s been in research for at least 15 years. Companies had made devices by about 10 years ago but the storage capacities were low so they weren’t that useful for consumer applications at that point. The hard problem with HAMR is dissipating the heat.