By Staff c.1998 The Economist
> Katzive says that in the geek humor of hard-disk engineers, the NT in
>Windows NT stands for ``Needs a Terabyte.'' He is only half-joking.
(I love this guy!)
Pity the poor engineers who build hard-disk drives for computers. For
years they have worked miracles to squeeze ever more data into ever smaller
and cheaper packages. Yet they are forever being upstaged by their more
glamorous colleagues in the chip-making business.
Perhaps that is understandable. Computer buyers, like car buyers, tend to
be more interested in speed than luggage space.
But in many ways the achievements of the magnetic-storage industry -- a
business which, according to Disk/Trend, a consultancy based in Mountain
View, Calif., is currently worth $34 billion a year -- are the more
impressive.
The amount of data that can be squirrelled away on a square inch of disk
surface has increased by 60 percent every year since 1991. Over the same
period, the cost of storage capacity has fallen from more than $5 a
megabyte to a mere five cents.
Earlier this month IBM announced the latest downward twist in this
virtuous spiral: ``Microdrive,'' a disk that packs 340 megabytes of data
(roughly equivalent to 340 copies of the 445-page Starr report) into a
cartridge smaller than a book of matches.
This is made possible by the latest ``giant magneto-resistive'' (GMR)
technology, laboratory versions of which can store as much as 1,450
megabytes a square inch.
However, despite such continuing triumphs of storage wizardry, the end is
now in sight. That end is the so-called superparamagnetic limit. It is a
consequence of the way that data are recorded on a hard drive.
The zeros and ones of digital information are preserved as tiny spots
organized in concentric tracks on the surface of a rapidly spinning disk
coated with a thin film of magnetic material. The alignment of north and
south magnetic poles in a spot tells a reading head whether the spot is a
zero or a one.
Alternatively, running an electric current through the head can alter the
polarity of a spot, and thus the message that it carries.
Over the years, engineers have increased storage densities by making these
magnetized spots smaller and then packing them more closely together. GMR
helps by detecting the effect of the spots' magnetism on the resistance of
a tiny wire in the reading head (previousLy yt has been the current induced
in the wire by a magnetic spot moving underneath it that has been detected,
a less sensitive process).
Other improvements have included new, more powerful magnetic-disk
coatings; changes in the shapes of the spots; moving the head closer to the
disk's surface so as to see the newly miniaturized spots more clearly; and
clever signal-processing techniques to detect the spots' ever-tinier
magnetic fluctuations.
Ultimately, however, these shifts are merely postponing the inevitable --
the point at which the spots become so small that they are magnetically
unstable, and thus liable to flip their north-south polarity at random in
response to heat-induced vibrations.
This is the superparamagnetic limit. Pass it, and any recorded data will
rapidly be lost.
Bob Katzive, Disk/Trend's vice-president, believes the limit will be
reached by 2003-04. Admittedly, disks should by then have achieved a
capacity of some 8,000 megabytes (8 gigabytes) a square inch. But
experience suggests that the demand for storage will keep growing
indefinitely. Overcoming the superparamagnetic limit is therefore a matter
of pressing concern.
One possible way forward is to borrow from the field of
``magneto-optical'' (MO) storage. This works on a different principle from
straight magnetic storage, for although the information is recorded
magnetically, it is written and read by a laser.
MO disks are coated with a material whose polarity can be altered only at
high temperatures. Information is written on to the disk by using the laser
to heat a tiny spot on its surface and then applying a magnetic field.
As the spot cools, it adopts the field's north-south polarity. Retrieving
the stored data involves bouncing the laser beam (at a lower power) off the
surface of the disk. The magnetic polarity of a dot affects its physical
characteristics enough for the reflected laser light to differ, depending
on whether it is bouncing off a north or a south pole.
Because the dots are magnetically stable at room temperature, MO
technology should ultimately be capable of holding more information than
conventional magnetic storage. Packing the dots more closely then becomes a
matter of optics: focusing and guiding the laser beam.
One such scheme has been developed by TeraStor, a recently founded company
based in San Jose, Calif. Its main technology is called near-field
recording. In this, the head is fitted with a special lens, and is brought
extremely close to the surface of the disk. The result is a tightly focused
beam, and thus a tiny spot.
The first product to use this technology -- a removable disk with a
capacity of 20 gigabytes -- should be available next year. After that,
TeraStor believes its technology will be able to keep up the 60 percent
annual increase in storage density that the industry has come to expect
long after conventional hard disks hit the superparamagnetic limit.
According to Gordon Knight, the company's chief technical officer, storage
densities as great as 37.5 gigabytes a square inch should be possible. That
would allow a single disk to carry the magic figure of a terabyte (1,000
gigabytes).
A different approach is being taken by Quinta, another San Jose startup.
Its Optically Enhanced Winchester scheme also involves MO. The vital twist
is the use of a tiny mirror which can be rotated with great precision by
passing an electric current through it. This mirror directs the laser on to
the surface of the disk.
Such fine control of the beam will, according to Quinta, allow the tracks
of data to be packed more tightly together on a disk than would be possible
if a conventional motor were used to position the laser. That should make
storage densities of up to 31 gigabytes a square inch possible.
The outside chance that one of these two companies has the answer for the
next generation of mass storage has already attracted backers from the
established hard-disk industry -- despite the fact that neither has yet
demonstrated that its approach can significantly outperform traditional
magnetics.
TeraStor is backed by Quantum, a leading disk-drive manufacturer. Last
year Seagate, another drive manufacturer, paid $325m for Quinta.
Not everyone, however, is convinced that either approach, snazzy though
each is, will prove profitable. One sceptic is Currie Munce, director of
storage-systems technology at IBM's Almaden research centre. He says that
IBM has already evaluated and rejected the near-field recording techniques
now being championed by TeraStor. He also suggests that conventional
magnetic-disk technology could hold out longer than expected, reaching
storage densities as great as 12.5 gigabytes a square inch.
By that time totally new technologies that IBM is working on -- such as
holographic cubes -- may be available.
But even IBM is not infallible. Its early support for Microsoft was
ultimately responsible for that company's massive ``bloatware'' operating
systems, which now run most personal computers, and which have helped to
fuel demand for huge disk capacities in the first place.
Katzive says that in the geek humor of hard-disk engineers, the NT in
Windows NT stands for ``Needs a Terabyte.'' He is only half-joking.
--"The public wants what the public gets, but I don't want what society's got" - Paul Weller
<> tbyars@earthlink.net <> --============_-1305899936==_ma============ Content-Type: text/enriched; charset="us-ascii"
By Staff c.1998 The Economist
<excerpt> Katzive says that in the geek humor of hard-disk engineers, the NT in Windows NT stands for ``Needs a Terabyte.'' He is only half-joking.
</excerpt>
(I love this guy!)
Pity the poor engineers who build hard-disk drives for computers. For years they have worked miracles to squeeze ever more data into ever smaller and cheaper packages. Yet they are forever being upstaged by their more glamorous colleagues in the chip-making business.
Perhaps that is understandable. Computer buyers, like car buyers, tend to be more interested in speed than luggage space.
But in many ways the achievements of the magnetic-storage industry -- a business which, according to Disk/Trend, a consultancy based in Mountain View, Calif., is currently worth $34 billion a year -- are the more impressive.
The amount of data that can be squirrelled away on a square inch of disk surface has increased by 60 percent every year since 1991. Over the same period, the cost of storage capacity has fallen from more than $5 a megabyte to a mere five cents.
Earlier this month IBM announced the latest downward twist in this virtuous spiral: ``Microdrive,'' a disk that packs 340 megabytes of data (roughly equivalent to 340 copies of the 445-page Starr report) into a cartridge smaller than a book of matches.
This is made possible by the latest ``giant magneto-resistive'' (GMR) technology, laboratory versions of which can store as much as 1,450 megabytes a square inch.
However, despite such continuing triumphs of storage wizardry, the end is now in sight. That end is the so-called superparamagnetic limit. It is a consequence of the way that data are recorded on a hard drive.
The zeros and ones of digital information are preserved as tiny spots organized in concentric tracks on the surface of a rapidly spinning disk coated with a thin film of magnetic material. The alignment of north and south magnetic poles in a spot tells a reading head whether the spot is a zero or a one.
Alternatively, running an electric current through the head can alter the polarity of a spot, and thus the message that it carries.
Over the years, engineers have increased storage densities by making these magnetized spots smaller and then packing them more closely together. GMR helps by detecting the effect of the spots' magnetism on the resistance of a tiny wire in the reading head (previousLy yt has been the current induced in the wire by a magnetic spot moving underneath it that has been detected, a less sensitive process).
Other improvements have included new, more powerful magnetic-disk coatings; changes in the shapes of the spots; moving the head closer to the disk's surface so as to see the newly miniaturized spots more clearly; and clever signal-processing techniques to detect the spots' ever-tinier magnetic fluctuations.
Ultimately, however, these shifts are merely postponing the inevitable -- the point at which the spots become so small that they are magnetically unstable, and thus liable to flip their north-south polarity at random in response to heat-induced vibrations.
This is the superparamagnetic limit. Pass it, and any recorded data will rapidly be lost.
Bob Katzive, Disk/Trend's vice-president, believes the limit will be reached by 2003-04. Admittedly, disks should by then have achieved a capacity of some 8,000 megabytes (8 gigabytes) a square inch. But experience suggests that the demand for storage will keep growing indefinitely. Overcoming the superparamagnetic limit is therefore a matter of pressing concern.
One possible way forward is to borrow from the field of ``magneto-optical'' (MO) storage. This works on a different principle from straight magnetic storage, for although the information is recorded magnetically, it is written and read by a laser.
MO disks are coated with a material whose polarity can be altered only at high temperatures. Information is written on to the disk by using the laser to heat a tiny spot on its surface and then applying a magnetic field.
As the spot cools, it adopts the field's north-south polarity. Retrieving the stored data involves bouncing the laser beam (at a lower power) off the surface of the disk. The magnetic polarity of a dot affects its physical characteristics enough for the reflected laser light to differ, depending on whether it is bouncing off a north or a south pole.
Because the dots are magnetically stable at room temperature, MO technology should ultimately be capable of holding more information than conventional magnetic storage. Packing the dots more closely then becomes a matter of optics: focusing and guiding the laser beam.
One such scheme has been developed by TeraStor, a recently founded company based in San Jose, Calif. Its main technology is called near-field recording. In this, the head is fitted with a special lens, and is brought extremely close to the surface of the disk. The result is a tightly focused beam, and thus a tiny spot.
The first product to use this technology -- a removable disk with a capacity of 20 gigabytes -- should be available next year. After that, TeraStor believes its technology will be able to keep up the 60 percent annual increase in storage density that the industry has come to expect long after conventional hard disks hit the superparamagnetic limit.
According to Gordon Knight, the company's chief technical officer, storage densities as great as 37.5 gigabytes a square inch should be possible. That would allow a single disk to carry the magic figure of a terabyte (1,000 gigabytes).
A different approach is being taken by Quinta, another San Jose startup. Its Optically Enhanced Winchester scheme also involves MO. The vital twist is the use of a tiny mirror which can be rotated with great precision by passing an electric current through it. This mirror directs the laser on to the surface of the disk.
Such fine control of the beam will, according to Quinta, allow the tracks of data to be packed more tightly together on a disk than would be possible if a conventional motor were used to position the laser. That should make storage densities of up to 31 gigabytes a square inch possible.
The outside chance that one of these two companies has the answer for the next generation of mass storage has already attracted backers from the established hard-disk industry -- despite the fact that neither has yet demonstrated that its approach can significantly outperform traditional magnetics.
TeraStor is backed by Quantum, a leading disk-drive manufacturer. Last year Seagate, another drive manufacturer, paid $325m for Quinta.
Not everyone, however, is convinced that either approach, snazzy though each is, will prove profitable. One sceptic is Currie Munce, director of storage-systems technology at IBM's Almaden research centre. He says that IBM has already evaluated and rejected the near-field recording techniques now being championed by TeraStor. He also suggests that conventional magnetic-disk technology could hold out longer than expected, reaching storage densities as great as 12.5 gigabytes a square inch.
By that time totally new technologies that IBM is working on -- such as holographic cubes -- may be available.
But even IBM is not infallible. Its early support for Microsoft was ultimately responsible for that company's massive ``bloatware'' operating systems, which now run most personal computers, and which have helped to fuel demand for huge disk capacities in the first place.
Katzive says that in the geek humor of hard-disk engineers, the NT in Windows NT stands for ``Needs a Terabyte.'' He is only half-joking.
--
"The public wants what the public gets,
but I don't want what society's
got" - Paul Weller
<<> tbyars@earthlink.net <<>
--============_-1305899936==_ma============--