The 1998 the Nobel Prize in Physics was awarded to Robert Laughlin, Horst Störmer, and Daniel Tsui for the discovery and explanation of the fractional quantum Hall effect (FQHE). Their work, performed using gallium arsenide heterostructures, showed that the Hall conductance of 2D electrons shows precisely quantised plateaus at fractional values.

In 1982, when Stormer and Tsui were experimenters at Bell Labs, they and their colleague Arthur Gossard discovered this totally unexpected quantum effect in the transport properties of two‐dimensional electron 'gases' at low temperature in strong magnetic fields. A 1983 paper by Laughlin, describing the discoveries was published in Physical Review Letters 50, 1395.

The 1980's explanation of the effect, however, is now disputed - and the microscopic origin of the FQHE is currently considered unknown - remaining a major research topic in condensed matter physics.

Several theories attempt to explain the effects, but none has yet gained full acceptance.

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