Fractional quantum Hall effect

The fractional quantum Hall effect (FQHE) is a physical phenomenon in which the Hall conductance of 2D electrons shows precisely quantised plateaus at fractional values of ${\displaystyle e^{2}/h}$. It is a property of a collective state in which electrons bind magnetic flux lines to make new quasiparticles, and excitations have a fractional elementary charge and possibly also fractional statistics. The 1998 Nobel Prize in Physics was awarded to Robert Laughlin, Horst Störmer, and Daniel Tsui for the discovery and explanation of the fractional Hall effect. However, Laughlin's explanation was a phenomenological guess and only applies to fillings ${\displaystyle \nu =1/m}$ where ${\displaystyle m}$ is an odd integer. The microscopic origin of the FQHE remains unknown and is a major research topic in condensed matter physics.

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