Two-dimensional electron liquid and the fractional quantum Hall effect
Why do electrons confined to two dimensions in a strong magnetic field condense into exotic liquid states carrying fractionally charged, sometimes non-abelian, quasiparticles?
History and references
Partly settled. Some of it is understood, some is still argued about.
Ginzburg's problem #4 highlighted the (then-recent, 1998 Nobel-winning) fractional quantum Hall effect. The basic theoretical framework (Laughlin wavefunctions, fractionally charged quasiparticles) was already established and experimentally confirmed via shot-noise measurements by 1997. Since 1999 the frontier has moved to directly observing anyonic braiding statistics of these quasiparticles (achieved in 2020 experiments) and to non-abelian candidate states (e.g. the nu=5/2 plateau) that are pursued as building blocks for topological quantum computers — this extended frontier remains active research.
A flat world of electrons in a magnetic field spontaneously invents particles that carry an exact fraction of the electron's charge.
References
- What problems of physics and astrophysics seem now to be especially important and interesting (thirty years later, already on the verge of the XXI century)?, V L Ginzburg, Physics-Uspekhi 42 (4) 353-373, 1999
- The Nobel Prize in Physics 1998, NobelPrize.org press release, 1998
- Fractional statistics in anyon collisions, H. Bartolomei et al., Science 368, 173, 2020
Solutions 0
Sign in or create an account to publish a solution