Researchers to Share Ledlie Prize

Two chemistry professors and one physics professor will share this year's George Ledlie Prize, awarded by the University for superior research.

Charles M. Lieber and Stuart L. Schreiber, both professors of chemistry, and David R. Nelson, Mallinckrodt professor of physics, were nominated for the $7,000 prize by Dean of the Faculty Jeremy R. Knowles.

"I am delighted to be recognized by my colleagues on the Faculty [of Arts and Sciences] in this way," Nelson said.

Schreiber's research will hopefully lead to designing better "gene therapy" and understanding genetic disease. Nelson and Lieber's work may help in the engineering of levitated trains and making magnetic resonance imagers (MRIs) smaller and more efficient.

Nelson, a theorist, and Lieber, who primarily conducts experiments, worked together to discover how superconducting materials can be made to "work better in an intense magnetic field," Nelson said.

Superconducting materials, when cooled to below 100 degrees Kelvin, can carry current without any resistance. This means that once a current is being driven around a circuit of superconducting material, it no longer requires a voltage source to continue its motion.

However, "anytime you have a superconductor in a magnetic field... it tends to destroy the phenomenon: the zero resistance," Nelson said.

As a magnetic field passes through a superconductor, the magnetic field bunches up into lines. Previously, these lines had caused a problem because they acted like "wiggly strings," said Nelson.

As the lines wiggle through the material in the presence of an electric current, the dissipated heat can cause the source of the magnetic field to melt if it is not cooled. But cooling is currently a financially inefficient solution.

Nelson explained that by "shooting ions" through the material first, it creates columnar paths through which the flux lines will move. When they move in these straight lines, less heat is dissipated.

Nelson explained that since such materials would be easier to cool, his "dream" is an MRI "similar to Star Trek, the size of a hand-held calculator," rather than the current MRIs which are the size of a small room which often disturb claustrophobic patients.

In addition, he hopes to see his ideas lead to the engineering of levitated trains which would move more efficiently by floating above the track.

While Nelson developed some of the theory behind these new techniques, Lieber has been working to synthesize new materials, including carbon nitride, a substance perhaps harder than diamond, which could be used for protective coatings and new cutting tools, according to the Harvard Gazette.

Schreiber has researched how a variety of proteins work with cell DNA to turn cell activities on and off, the Gazette said.

Schreiber could not be reached for comment on his work.

It is hoped that his contribution will facilitate medical treatments in which working genes can be substituted for those which are not functioning properly.