Robert Betts Laughlin
active c. 1950, Visalia, California, United States
American theoretical physicist who explained the fractional quantum Hall effect through the quantum-liquid wavefunction that bears his name.
Laughlin studied at UC Berkeley and earned his PhD at MIT in 1979. He worked at Lawrence Livermore National Laboratory and Bell Labs before joining Stanford University in 1985, where he was professor of physics until retirement.
In 1983, one year after Störmer and Tsui observed the fractional quantum Hall effect, Laughlin proposed a many-body wavefunction describing an incompressible quantum liquid with fractionally charged excitations. The work earned him the 1998 Nobel Prize in Physics. He later wrote extensively on emergence and the limits of reductionism in physics.
Nobel-winning work
In 1982 Horst Störmer and Daniel Tsui found that at extremely strong magnetic fields and near absolute zero, the two-dimensional electron gas in GaAs/AlGaAs heterostructures shows Hall resistance quantized at fractional filling factors such as ν = 1/3 — the fractional quantum Hall effect.
Laughlin explained the phenomenon in 1983 with a new many-body wavefunction — the 'Laughlin wavefunction' — describing an incompressible quantum liquid in which Coulomb repulsion condenses the electrons into a collective state. Its excitations are quasiparticles carrying fractional charge e/3, a prediction later confirmed experimentally. The Nobel committee described the trio's work as the discovery of 'a new form of quantum fluid with fractionally charged excitations'.
Workplaces: Stanford University, Bell Labs
United States