A series of STM images showing the numbers 0 through 10 represented by single carbon-60 molecules (buckyballs) on a copper surface. The top row shows zero, with no molecules at the end of the row, and the successive rows provide representations of the numbers 1-10, with the appropriate numbers of molecules at the end of each row. (Image courtesy IBM Zurich Research Laboratory.)
Researchers at the IBM Zurich Research Laboratory in Switzerland have constructed a nanoscale abacus, a room-temperature system for representing and manipulating numbers at the single-molecule level. Using a scanning tunneling microscope (STM), a device that can image and move individual atoms and molecules on a surface, James Gimzewski and his colleagues at IBM position carbon-60 molecules (buckyballs) on a copper surface. The carbon-60 molecules are sturdy and are constrained to move in a line between shallow copper "terraces." Although it is (currently) a slow process to manipulate numbers on the nanoscale abacus, its level of miniaturization is undeniable: hundreds of buckyball rows could fit neatly in a space the width of a typical feature on a Pentium chip.
This research was reported by M.T. Cuberes, R.R. Schlittler, and J.M. Gimzewski in Applied Physics Letters, 11 November 1996.
Link to related Physics News Update item (Available November 6, 1996)