The field theory of Skyrme lattices in quantum Hall ferromagnets

Дата и время публикации : 1997-05-22T10:26:58Z

Авторы публикации и институты :
M. Abolfath
M. R. Ejtehadi

Ссылка на журнал-издание: Phys.Rev. B58 (1998) 10665
Коментарии к cтатье: 17 pages
Первичная категория: cond-mat.mes-hall

Все категории : cond-mat.mes-hall

Краткий обзор статьи: We report the application of the nonlinear $sigma$ model to study the multi-skyrmion problem in the quantum Hall ferromagnet system. We show that the ground state of the system can be described by a ferromagnet triangular Skyrme lattice near $nu=1$ where skyrmions are extremely dilute. We find a transition into antiferromagnet square lattice by increasing the skyrmion density and therefore $|nu-1|$. We investigate the possibility that the square Skyrme lattice deforms to a single skyrmion with the same topological charge when the Zeeman energy is extremely smaller than the Coulomb energy. We explicitly show that the energy of a skyrmion with charge two is less than the energy of two skyrmions each with charge one when $g leq g_c$. By taking the quantum fluctuations into account, we also argue the possibility of the existence of a non-zero temperature Kosterlitz-Thouless and a superconductor-insulator phase transition.

Category: Physics