ANNNI model

ANNNI model

The abbreviation ANNNI model stands for 'Axial Next-Nearest Neighbor Ising model'. It is a highly cited variant of one of the best known models in statistical physics, the Ising model. In that variant, competing ferromagnetic and
antiferromagnetic exchange interactions are coupling spins at nearest and next-nearest neighbor sites, along one of the crystallographic axes of the lattice. The model is describing in a prototypical fashion fascinating and complicated spatially modulated magnetic superstructures in
crystals.

The model was introduced in 1961 by (Sir) Roger Elliott from the University of Oxford, but only several years later, many of its intriguing properties had been analyzed and established (especially by Per Bak, Michael E. Fisher, Walter Selke, and Jacques Villain), providing a theoretical basis for understanding numerous experimental observations on commensurate and incommensurate structures, aswell as accompanying phase transitions, in magnets, alloys, adsorbates, and other solids.

References

*cite journal
author = M.E. Fisher and W. Selke
date = 1980
title = Infininitely many commensurate phases in a simple Ising model
journal = Phys. Rev. Lett.
volume = 44
pages = 1502–1505
doi = 10.1103/PhysRevLett.44.1502

*cite journal
author = P. Bak
date = 1982
title = Commensurate phases, incommensurate phases, and the devil's staircase
journal = Reports on Progress in Physics
volume = 45
pages = 587–629
doi = 10.1088/0034-4885/45/6/001

*cite journal
author = W. Selke
date = 1988
title = The ANNNI model
journal = Physics Reports
volume = 170
pages = 213–264
doi = 10.1016/0370-1573(88)90140-8


Wikimedia Foundation. 2010.

Игры ⚽ Поможем написать курсовую

Look at other dictionaries:

  • ANNNI-Modell — Die Abkürzung ANNNI Modell steht für Axial Next Nearest Neighbor Ising Modell. Es handelt sich um eine Variante des in der Statistischen Mechanik bekannten Ising Modells. In dem Modell wird angenommen, dass konkurrierende ferro und… …   Deutsch Wikipedia

  • Ising model — The Ising model, named after the physicist Ernst Ising, is a mathematical model in statistical mechanics. It has since been used to model diverse phenomena in which bits of information, interacting in pairs, produce collectiveeffects.Definition… …   Wikipedia

  • Michael E. Fisher — Michael Ellis Fisher (* 3. September 1931 in Trinidad, Westindien) ist ein Theoretischer Physiker. Er hat bahnbrechende Beiträge zur Statistischen Physik, insbesondere zur Theorie der kritischen Phänomene und Phasenübergänge, geleistet. Diese… …   Deutsch Wikipedia

  • Geometrically frustrated magnet — Geometrical frustration and ice rules The word frustration was introduced to describe the situation where a system cannot simultaneously minimize the interaction energies between its components [cite journal last = Schiffer first = P. authorlink …   Wikipedia

  • Michael Fisher — This article is about the British theoretical physicist. For others, see Michael Fisher (disambiguation). Michael Ellis Fisher Born 3 September 1931 (1931 09 03) (age 80) Trinidad …   Wikipedia

  • Antiferromagnetism — In materials that exhibit antiferromagnetism, the magnetic moments of atoms or molecules, usuallyrelated to the spins of electrons, align in a regular pattern with neighboring spins (on different sublattices) pointing in opposite directions. This …   Wikipedia

  • Singular function — The graph of the winding number of the circle map is an example of a singular function. In mathematics, a singular function is any function ƒ defined on the interval [a, b] that has the following properties: ƒ is continuous on [a, b]. (**) there… …   Wikipedia

  • Multiferroics — have been formally defined as materials that exhibit more than one primary ferroic order parameter simultaneously (i.e. in a single phase).[1] The four basic primary ferroic order parameters are ferromagnetism, ferroelectricity, ferroelasticity… …   Wikipedia

  • Ernst Ising — (* 10. Mai 1900 in Köln; † 11. Mai 1998 in Peoria/Illinois, USA) war ein deutscher Mathematiker und Physiker. Inhaltsverzeichnis 1 Leben 2 Wirkung 3 Literatur …   Deutsch Wikipedia

  • Geometrische Frustration — (auch kurz als Frustration bezeichnet) ist ein Phänomen in der Physik kondensierter Materie, in der die geometrischen Eigenschaften eines Kristallgitters oder die Anwesenheit miteinander im Konflikt stehender atomarer Kräfte die gleichzeitige… …   Deutsch Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”