December 2004 - Materials Science Institute - University of Oregon

IBM RESEARCH, ALMADEN RESEARCH CENTER (top); MICHA ASSCHER AND GABRIEL KERNER (bottom)
IMAGING
Daniel Rugar
Manager of nanoscale studies, IBM Almaden Research Center,
San Jose, Calif.
Made MRI details sharper than ever.
The power of magnetic resonance imaging (MRI) to peer into the
body rests on its ability to detect the spins of subatomic particles.
Even the best conventional MRI-based microscopes are sensitive
only to groups of at least one trillion nuclear spins, however, limiting
resolution to one micron. In the July 15 Nature, Daniel Rugar
and his colleagues reported detecting the spin of a single electron,
with rudimentary imaging at a resolution of just 25 nanometers.
Their technique combines MRI with a microscopic cantilever sensitive
enough to detect the infi nitesimal forces a single electron spin exerts. In the future,
Rugar hopes to pick up a single nuclear spin, whose signal is roughly 600 times weaker
than an electron’s, opening the door to microscopes yielding three-dimensional images
of molecules with atomic detail.
Gold lines on
a ruthenium surface demonstrate
the control exercised by a novel
patterning technique.
MANUFACTURING
Micha Asscher
Chemist, Hebrew University of Jerusalem
Demonstrated how to grow nanostructures
of nearly anything on anything else.
Assembling wires and other intricate structures on any surface can
prove tricky because not all materials combine well. If a substance is
built onto another with which it interacts weakly, the top layer can ball
up. Conversely, pairs of materials that interact strongly can bond too
tightly to weave into sophisticated patterns. In May, Micha Asscher
and his colleagues revealed a way to lay down a pattern of almost any
substance on any other for novel nanometer scale devices such as those
used in microelectronics and catalysts. Their method deposits a layer of
inert xenon—supercooled to a solid at roughly –250 degrees Celsius—
between two substances. When this sandwich is heated, the xenon
evaporates and the bottom layer absorbs the top one. The researchers
say their method could make conducting wires less than 30 nanometers
wide yet millimeters long.
SA 50
(research leaders)
Microscope plus MRI detects the
force of an electron’s spin.
MEDICAL DIAGNOSTICS
Francis Barany
Microbiologist, Weill Medical College
of Cornell University
Invented chips for rapid detection
of cancer and infections.
The mutations that lead to cancer can alter a
variety of genes and be nearly indistinguishable
from the normal DNA sequences around
them. Francis Barany is creating devices that
rapidly identify mutations to discover which
ones cause tumors, a strategy that should
enable more effective individualized cancer
therapies. Barany is a leader in inventing
critical technologies sensitive enough to work
at the level of single proteins or nucleotides,
the building blocks of DNA. Products based
on Barany’s patents have been developed by
Applied Biosystems, Celera Diagnostics and
New England Biolabs. In the past year, he
helped to start a biodefense consortium that
includes the Centers for Disease Control and
Prevention, the FBI and Argonne National
Laboratory, a collaboration intended to develop
quick, cheap and precise gene-based biosensors
to detect biowarfare pathogens.
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