I have a question about data storage in the hard
drives of computers. I was rreading an article
that said that at a certain small grain size, the
magnetic grains of a hardrive will spontaneously
loose their charge I was wondering whether or
not this affect would happen if the hardrive was
contained in a vacuum. If it is possible to
create such a small vacuum, then could it be
possible to use this idea to create a new,
extremely high capacity, hard drive using a vacuum?
Question Date: 2001-06-06
Answer 1:
The problem of spontaneous field inversion in
small magnetic grains is a collective
ferromagnetic property of the material -- it would
still occur in a vacuum. However, vacuum could not
work in current hard drives in any case, as the
head is suspended above the drive platter largely
by the fluid forces of the air or other gas in the
drive casing. Without this support, the head
would impact the disk (as it does when stopped in
Winchester designs). Magnetic disk drives are a
fascinating subject -- 25 years ago, everyone
thought that they'd be replaced by magnetic
bubbles in a couple of years. It didn't
happen... IBM has some of the best disk
technology in the world -- their web site is:
http://www.almaden.ibm.com/sst/
