But even if that succeeds, Dr Likharev does not think that the single-electron transistor could ever survive the more demanding environment in a processor.

ECONOMIST: The transistor��s heir

In December, a group led by Stephen Chou at the University of Minnesota announced that it had got a single-electron transistor to work albeit unreliably at room temperature.

ECONOMIST: The transistor��s heir

Konstantin Likharev, at the State University of New York at Stony Brook, a co-inventor of the single-electron transistor, is working on ways to combine it with conventional transistors to make super-dense memory chips.

ECONOMIST: The transistor��s heir

And in the current issue of Applied Physics Letters, a group led by Haroun Ahmed at the Hitachi Cambridge Laboratory in Britain reports another vital step, a single-electron transistor that, for the first time, amplifies its input signal (though only by a factor of 3.7, several hundred times more weakly than a conventional transistor does).

ECONOMIST: The transistor��s heir