CMP Seminar

Monday, September 16, 2002
4:10 p.m., Room 1400 BPS Building
Refreshments served at 3:45 p.m.


Cooking with Nanostructured Carbon
==================================

David Tomanek
Michigan State University
http:/www.pa.msu.edu/~tomanek/

The continuous reduction of device sizes, which is rapidly
approaching the atomic level, calls for new approaches to design
and test future building blocks of Nanotechnology. Massively
parallel supercomputers will become the most powerful tool to
interpret what happens on the nanometer scale, where quantum
phenomena dominate, and help describe unexpected behavior such as
a giant magnetoconductance[1]. At the nanometer scale, as I will
illustrate, structures of carbon may become stronger than steel,
yet turn into quantum conductors or even powerful magnets.

In nanostructures that form during a hierarchical self-assembly
process, even defects may play a different, often helpful role. An
efficient self-healing process may convert less stable atomic
assemblies into other, more perfect structures, thus answering an
important concern in molecular electronics. Defects may even be
used in nano-scale engineering to form complex systems such as
carbon foam [2] or nanotube peapods [3,4].

In this presentation, I will show how some of these challenging
problems can be most efficiently addressed in simulations on
recently available massively parallel supercomputers.

[1] Steven W.D. Bailey, David Tomanek, Young-Kyun Kwon, and Colin
J. Lambert, Giant magneto-conductance in twisted carbon nanotubes,
Europhys. Lett. 59, 75 (2002).

[2] Koichiro Umemoto, Susumu Saito, Savas Berber, and David
Tománek, Carbon foam: Spanning the phase space between graphite
and diamond, Phys. Rev. B 64, 193409 (2001).

[3] Young-Kyun Kwon, David Tománek, and Sumio Iijima,
"Bucky-Shuttle" Memory Device: Synthetic Approach and Molecular
Dynamics Simulations, Phys. Rev. Lett. 82, 1470 (1999).

[4] Savas Berber, Young-Kyun Kwon, and David Tománek, Microscopic
Formation Mechanism of Nanotube Peapods, Phys. Rev. Lett. 88,
185502 (2002).