European researchers have developed a HDD using nanospheres of silica as a support to carry the magnetic data, which decreases the size of a bit and ipso facto raise the disk capacity.

A typical HDD saves data in binary on the playing field magnetic cell composed of 60-80 small particles of about 7 nm which are present in the ferromagnetic disk. If you want to raise the capacity of the disk, it can decrease the size of the cell, but the signal noise raises the risk of error. It can also shrink the particle size, but must contend with an unstable system.

Finally, we get a disk with a density of 1 TB per square inch and the researchers hope to further shrink the size of these spheres. No one talks about marketing, but the manufacturing processes used are quite standard, which is a good indication for the future of this technology.