18:00 30 April 2008NewScientist.com news service
Nanoscale circuits based on molecules used in sunscreen lotion have led to the discovery of the "missing link" of electronics engineering – a previously mythical device known as a "memristor".
First predicted in 1971, the memristor could help develop denser memory chips or even electronic circuits that mimic the synapses of the human brain, says Stan Williams who made the discovery with colleagues at Hewlett-Packard's lab in Palo Alto, California.
Since electronics was developed, engineers have made circuits using combinations of three basic elements – resistors, capacitors and inductors.
But in 1971, a young circuit designer called Leon Chua at the University of California, Berkeley, realised something was missing. He was toying with the non-linear mathematics that describes how the four variables in a circuit – voltage, current, charge and flux – behave in the three basic elements.
