Francois Leonard

Léonard’s experience with carbon nanotubes began when the field was just emerging. While the discovery of carbon nanotubes is credited to Japanese physicist Sumio Iijima in 1991, work on applications didn’t begin until the late 1990s. Léonard was at IBM as a postdoc when researchers there built the first transistor from carbon nanotubes. As a theoretical physicist, Léonard was working in uncharted territory. From the beginning, he worked on modeling approaches to understand how carbon nanotubes might behave in certain applications. He joined Sandia in 2000, where he has continued his carbon nanotube research. The semiconducting side of carbon nanotubes holds a lot of promise for the development of new nanoelectronic devices. “A carbon nanotube creates a transistor that is only one nanometer wide,” says Léonard. “This makes it possible, in principle, to achieve very high device densities compared with the current state of the art.” The field emission properties of carbon nanotubes are also exciting. Flat panel displays are typically made from a high density of sharp tips, to which high voltage is applied to extract electrons. These electrons strike and activate the pixels in the screen. Carbon nanotubes can serve this purpose because they are very sharp, long, and can sustain high fields and high temperatures.