Hydrogen, the simplest atom, consists of a single proton encircled by a single electron.

ECONOMIST: Biochemistry

In diamonds, the six-electron atoms share a single electron with each of the four atoms that abut them, forging the strongest bond known to chemists and making diamonds among the hardest minerals.

FORBES: Fracture Lines

In addition, since a single electron travelling through the device emits light not once (as in most other lasers), but many times, quantum cascade lasers are powerful: Dr Capasso's group has recently shown that they beat conventional semiconductor lasers by a factor of 20.

ECONOMIST: Lasers

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

Andrew Kent, a physicist at New York University, spends most days running electricity through a magnet smaller in diameter than a single cell, trying to determine the lowest current at which an electron's spin changes orientation.

FORBES: Magazine Article