The Nobel Prize in Physics 1998


	Bursting bounds Mobile telephones, satellite TV, the Net, the globalised economy and politics: the world is changing. Knowledge of electrons is a key to the events and the processes of our time. Soon the circuits used will be so small that quantum fluids with different types of quasi-particles may become forces to be reckoned with in everyday computers. The discovery recognised with this year's Nobel Prize in Physics may well turn out to be essential for our future information society.
	Knowledge in leaps Horst Störmer and Daniel Tsui did similar experiments simultaneously with von Klitzing's. They used extremely pure semi-conductors - built atom-by-atom - cooled them to very near absolute zero and used the world's strongest magnet. In 1982 they suddenly saw entirely new plateaux in the Hall effect. According to the theories of the time this sort of misbehaviour was impossible. Not surprisingly Störmer and Tsui, and those arond them, had their doubts at first. But this is also the stuff that science is made of. Suddenly somebody does an experiment with a result that forces us to look at the world with new eyes - and search for new theoretical models.
	Eddies in the storm Robert Laughlin searches for an explanation for Störmer's and Tsui's discovery. After a year's thinking and calculating, his model is complete. It resembles a storm at sea, in which the force of the magnetic wind and the electrons of the quantum fluid create entirely new phenomena - eddies and waves - without being changed themselves.

In the icy doldrums near absolute zero and in the iron hand of the magnetic field the electrons in the atom-thin layer are forced to cooperate and form a quantum fluid. As the field changes, eddies form in the fluid. The electrons are compelled to divide their charges among the eddies. As they swirl, the compressions and rarifications behave like particles - quasi-particles - each bearing a fraction of the electron's charge.

Hailstones on the roof

Electrons in a conductor can rattle like hailstones on a roof, one blow for each electron. Quasi-particles, then, should rattle with a fraction of the sound of a whole electron. In 1997 the quasi-particles made themselves heard, proving directly that they exist. Researchers in Israel and France succeeded in designing instruments that could "listen" to the fractional noise of quasi-particles.

Quasi-particles with fractional charges - a crack in Landau's foundation.

Contents:
Introduction » Practice and theory » The Laureate's discoveries and their significance » Further reading »
Based on materials from the 1998 Nobel Poster for Physics. Credits and references for the poster »