Electron beam hard drive technology?

` Today, I found this while skimming through one of the Nature publications and said: "Yay!" As much as I still love my Western Digital:

...Eric C. Hannah and Michael A. Brown have now been granted a US patent, filed by Intel Corporation, on reading as well as possibly writing magnetic data using a spin-polarized electron beam instead of magnetic field sensors¹.
` Their concept makes use of a hard magnetic layer, sandwiched between half-metallic, soft magnetic 'spin mirrors'. At the appropriate beam energies, the mirror layers reflect electrons with minority spin polarization while being transparent for electrons polarized in the same direction as the magnetic layer. The electrons passing through the device will eventually be absorbed by the magnetic layer, and can then be detected, for example, through their optical recombination in an adjacent semiconductor layer.
` Although no proof of concept has been provided, a system like this could soon lead to the abolishment of the slow read/write heads in use today.

` Yes, I think it is time for hard drives to stop reading in microseconds and speed up to... what? Nanoseconds? Picoseconds? That leaves more time for doing other things not computer-related...