From the Summer 2001 Issue
SCIENCE & TECHNOLOGY

NANOTECHNOLOGY
It's a small, small world
By Emily Chung
Jody
Mandeville and Christina Kaiser spend their days drawing patterns
too small to see with anything but a very powerful electron
microscope.
The size of their work is no indication of its importance since
these patterns could soon be used to precisely control the colour,
direction and movement of light waves within optical cables
and networks. It is technology that will allow the Internet
to transmit multiple video and audio streams to your computer
simultaneously at ultra-high speeds.
Nanolab is what Kaiser and Mandeville call their workspace at
the University of British Columbia (UBC) in Vancouver. Their
minuscule works of science are part of a growing field known
as nanotechnology.
Nanotechnology
is the science of making, studying, and working with things
on a nano-scale - in other words, really, really small. A nanometre
is a millionth of a millimetre. A single human hair is almost
100 000 nanometres wide.
"The idea is, if you deal with materials and structures
on that scale, they don't behave like traditional things that
are larger because new phenomena occur," explains Harry
Eugen Ruda, Professor and Director of the Energenius Centre
for Advanced Nanotechnology (ECAN) at the University of Toronto.
We are all familiar with the behaviour of objects our size and
the Newtonian rules of physics they follow but when things get
really small and quantum rules take over, entirely new possibilities
open up.
To illustrate this, if you threw a ball against a wall it would
probably bounce off and come back to you. However, if the ball
were less than a nanometre in diameter things would be quite
different: when it hit the wall it would tunnel in the quantum
scheme. That means it could actually disappear through the wall
and come out the other side.
Too weird to be true? Maybe not. Devices have already been invented
to take advantage of electron tunnelling. One of them is the
Scanning Tunnelling Microscope (STM), one of the most valuable
tools available to nanotechnology researchers. Gerd Binnig and
Heinrich Rohrer won the Nobel Prize in physics in 1986 for having
invented this simple but amazing machine only four years earlier.
With the STM, researchers can look at individual atoms, and
pick them up and move them around.
It
all sounds like the stuff of science fiction novels, but much
of it is close to becoming reality. Nanotechnology is in the
process of revolutionizing communications, computing, and medicine,
"Small devices could have applications well beyond simple
computing, and one of the most exciting areas in which it has
great potential is in medicine. There are a few functions which
I think are obviously on the horizon in the medical area,"
Ruda says optimistically, "for example, artificial senses:
artificial noses, the artificial retina, the artificial eye."
He also agrees with predictions that the technology to make
computer chips smaller and self-assemble small numbers of molecules
on a surface will soon make diagnostic sensors and biosensors
available to doctors. In fact, he suggests that it's not unrealistic
to imagine that these chips could actually be sent through our
blood vessels to target areas of the body and transmit their
findings back to a computer in the doctor's office via radio
waves.
It
seems obvious that nanotechnology is the wave of the future
and will become an intricate part of our everyday lives. "I
think nanotechnology will be the technology," says Ruda.
"By the time we look to 2010 it will all be nanotechnology
it's at the threshold of being totally pervasive."
Dealing with the phenomena of nanotechnology is becoming inevitable
in some fields. In particular, the computer industry is currently
pushing the physical limits of how much information we move
around and how fast we can do it using traditional methods.
"With the Internet, everyone wants real-time video, multiple
computers at home and different video and audio channels at
the same time," said Jeff Young, Assistant Professor in
the Physics Department at UBC. "So the more things people
want like that, the more technology we have to build into the
system."
Young has been studying properties of light, semiconductors
and electronics since his days as a graduate student. While
at UBC he saw an opportunity to complement the existing research
and started his work on nanostructures. "Nano can mean
all kinds of different things," says Young.

Photo courtesy of D. Carr and H. Craighead, Cornell
The nanoguitar. The world's smallest guitar
is 10 micrometers long -- about the size of a single cell --
with six strings each about 50 nanometers, or 100 atoms, wide.
Made by Cornell University researchers from crystalline silicon,
it demonstrates a new technology for a generation of electromechanical
devices that could have a variety of uses in fiber optics, displays,
sensors and electronics.
In
his lab, it refers to the size of the patterns Mandeville, Kaiser,
and the other students use to harness and control light. By
splitting light into thousands of colours, coding a different
stream of data in each one, and sending it all down the same
cable over long distances at the speed of light, researchers
of "photonic" nanotechnology hope to dramatically
raise the number of lanes - and the speed limit - on the information
highway.
But it's not good enough to move huge amounts of information
quickly if your computer can't handle it. Making things smaller
also happens to be the most logical route to greater computing
power and speed for two reasons, explains Ruda, "If the
distance between A and B are shorter, information will pass
faster which makes the circuit work quicker."
"The other reason," states Ruda, "is that when
you have things closer together, then you can pack more devices
on the same area of chip." And if computer chips shrink
down to a size where quantum effects can be harnessed, computing
as we know it may suddenly evolve into something quite different.
Still, no technology comes easily. Mandeville explains that
the work can be deeply frustrating, but both he and Kaiser feel
that when things work out, it's all worthwhile. "I get
a huge sense of satisfaction looking at the finished product,"
through an electron microscope, of course.

This big machine makes the little machines...
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