Spintronic Hard Drives?

It seems that every time we turn around there's news of technological breakthroughs that appear as if from an episode of Star Trek. New battery technologies that increase battery life by a factor of ten, 'transparent' aluminum, and medical imaging that rivals what even ten years ago would have seemed miraculous will soon become commonplace.

Goodness knows computer technologies have exploded, making computers ubiquitous, and the functions they perform seem like normal everyday events of which we take little notice. And now there's another that may make computer data storage even bigger while at the same time shrinking the physical size required to store that data. Say hello to spintronics.

Using spintronics--the storage of bits generated by the magnetic spin of electrons rather than their charge--a proof-of-concept shift register was recently demonstrated by IBM. The prototype encodes bits into the magnetic domain walls along the length of a silicon nanowire, or racetrack. IBM uses "massless motion" to move the magnetic domain walls along the nanowire for the storage and retrieval of information.

IBM's goal, based on spintronic patents filed as early as 2004, is to use the same square micron that currently houses a single SRAM memory bit, or 10 flash bits, and drill down into the third dimension to store spin-polarized bits on a sunken racetrack-shaped magnetic nanowire. Using an area of silicon 1 micron wide and 10 microns high, IBM said its first-generation racetrack would store 10 bits compared to one, thereby replacing flash memory. Eventually, it could store 100 bits in the same area, which is dense enough to replace hard-disk drives.

While there are presently solid state hard drives out there, they are flash based, expensive, and cannot hold the amount of data that present hard drives can. They also have a limited number times data can be written to them before they start 'wearing out'. But nanowire spintronic memory may be the basis for high density, high speed, large scale memory that will replace hard drives and reduce the bottleneck represented by electromagnetic-mechanical hard drives we use today. If the technology can be made cheaply and easily enough 'hard drives', if that's what we'll still call them, may storage capacities in the terabyte and petabyte range. That's a thousand to a million times more than drives can handle today.