Wigner crystal

A Wigner crystal is the crystalline phase of the electron , which was first predicted by Eugene Wigner in 1934 as the ground state of a system of interacting electrons. The electrons each occupy positions that are as far apart as possible. At a given density, this leads to the electrons being arranged in a regular grid. This phase occurs when the density and temperature of the electrons are sufficiently low.

Wigner crystals could be experimentally been realized only in two-dimensional (2D) situations: the one hand, for electrons on a film liquid helium , on the other hand, in the 2D electron gas at the interface between two semiconductors - heterostructures . In the 2D Wigner crystal, the electrons form a triangular lattice, as theoretically predicted in 1976 by Günther Meißner and colleagues.

A magnetic field perpendicular to the plane of the electrons can be used to more strongly localize the electrons (in the Landau levels ). This enables crystallization at higher electron densities.

literature

• Eugene Wigner: On the Interaction of Electrons in Metals. In: Physical Review . Vol. 46, No. 11, 1934, 1002-1011, doi : 10.1103 / PhysRev.46.1002 .
• Daijiro Yoshioka: The Quantum Hall Effect (= Springer Series in Solid-State Sciences. 133). Springer, Berlin et al. 1998, ISBN 3-540-43115-2 .

Web links

• Thorsten Krome: Crystals made of electrons
• Wigner Crystal ( Memento from November 20, 2008 in the Internet Archive )
• Classical Wigner crystals move on Physics World, January 2002