A Miniature Logic Gate in Nanospace

CHEMISTS IN NORTHERN Ireland and Japan have designed a fluorescent molecule that carries out a logical computation in the nanospace of a membrane ( J. Am. Chem. Soc. 2005, 127, 8920).The system operates as a two-input AND logic gate, in which two conditions must both be satisfied to produce an output. "The paper shows the true miniaturization capability of computation using molecules by achieving a logic operation inside a nanospace with a 3-nm radius," says A. Prasanna de Silva, a chemistry professor at Queen's University, Belfast, who carried out the work with University of Tokyo assistant professor of chemistry Seiichi Uchiyama and coworkers. "This is thehighest level miniaturization, by far, of a computational device. To the best of our knowledge, the smallest known silicon devices have features of 65 nm. Our paper also shows, for the first time, that membranes provide a fine host for synthetic computing molecules." The computation molecule ...