Silicon has ruled the microchip world for a long time now.
Right from the days of the 4004, till today’s PIIIs and P4s, it has had a key
role to play in the microchip revolution. But, question is, can it hold on? Can
it continue to provide the backbone to the next-generation processors? Or, would
we see the advent of smaller, faster, and more efficient alternatives?
That,
only time will tell. But, if recent developments in microchip technology are to
be believed, silicon’s days are numbered and the countdown has begun.
Researchers around the world have built molecular logic gates, which will form
the basis of what they call "Molecular Computers". These logic gates
function just like the logic gates used in today’s computers–the AND, OR,
NOT gates, etc, and the construction of these gates marks a huge step towards
the realization of the ultimate dream.
But, what are these "Molecular Computers"? Unlike
the current silicon chip-based computers, these computers are built on a
crystalline structure. This enables the computers to be so small that you might
not even notice them, even if one was lying right in front of your eyes.
Relative to current standards, these computers would be in the category of today’s
supercomputers, with computational power much, much higher than those of today’s
computers. And all this packed into a size so small, that you might actually
have trouble finding your computer if you kept it somewhere and forgot. To drive
home the point, consider the fact that a computer based on this technology could
pack the power of 100 workstations on the size of a grain of sand.
It’s believed that these computers will need far less power
than the current ones. Such a computer can potentially do approximately a 100
billion (1 followed, by 11 zeros) times better than a current Pentium in terms
of energy required to do a calculation. And this technology is not just
restricted to processors. Storage devices based on this technology may be able
to hold vast amounts of data permanently, doing away with the need to erase
files. Scientists further add that perhaps such computers will also be immune to
computer viruses, crashes, and other glitches. That’s a pleasant relief indeed
in today’s environment, where data is under constant threat from these and
various other factors.
The development of these logic gates has involved the hard
work and dedication of researchers at the University of California, Los Angeles
(UCLA) and Hewlett-Packard (HP). The first step in this direction was creating a
new compound, called rotaxane, which grows in a crystalline structure. Rotaxane
molecules, sandwiched between metal electrodes, functioned as logic gates.
Scientists working in this field seem to draw their inspiration from the most
powerful processor till today, built no thanks to them–the human brain. The
brain uses very little energy, and yet it has billions of delicate
interconnections. This is why humans and animals can perform complex tasks such
as pattern recognition, which are very difficult for traditional,
semiconductor-based computers.
The information that today’s computers carry is etched on
to them, because of the fact that they are based on silicon chips. And it’s
becoming harder and harder to do this precisely on ever-smaller chips. What’s
more, as the size of transistors decreases from around 90 nanometres (0.00000009
metres) currently, to below 50 nanometres in future, the electrons start to obey
the laws of quantum physics. This will leave these devices useless and also
imposes a limit on how small these devices can be, forcing us to search for
alternatives. On the other hand, molecular computers are devoid of any such
problems, being based on a crystalline structure. A crystal can absorb
information, in the form of an electrical charge, and organize it more
efficiently than traditional silicon-based semiconductor devices. What’s more,
this imposes no restriction on the size of the device, which can, quite
literally be, as small as a grain of dust. Or they could be woven into your
clothing or painted on to the walls–imagine walking around with hundreds of
supercomputers all over your body.
The next step will be structuring the chip. Instead of
etching this structure on to the surface, as is done now with silicon chips, it’ll
be downloaded electrically. All the complexity of the chip could be downloaded
easily, via a wire attached to a bigger computer, which would provide the
structure to our crystalline chip, but for a small problem. The currently
available wires are too big, much bigger than the rotaxane molecules for us to
be able to do this. So scientists are now on to the task of shrinking the wires
until they are the same diameter as the molecules, and then we’ll have the
miniaturized technology. Another alternative is the possible use of carbon
nanotubes, long, thin tubes made of pure carbon. Also known as "Bucky
tubes" they are no thicker than most molecules.
But what has excited people all around the world is the wide
variety of uses such computers could be put to, doing tasks modern day computers
can’t even come close to doing. Such chips could, for example, have
unbelievable applications in the field of medicine. Such a microscopic sensor
could come along side a particular breed of bacteria and, quite possibly,
identify the bacteria or disease from inside the body and could feasibly be used
to administer medications internally. Also, an auxiliary, biologically-based
processor may quite possibly be capable of recognizing hazardous materials or
perform really complex tasks, such as identifying spending patterns on credit
applications. Ultimately we’ll have computers approaching and, quite possibly,
even surpassing the power of the human brain. Vast improvements in disease
prevention, diagnosis and treatment will increase life expectancy. These
non-power hungry computers will leave us cheaper and more abundant energy.
But, wait don’t cancel the order of that Athlon, not just
yet. A prototype of a molecular computer won’t be ready for at least another
five years, which you could buy ten years from now.