Spin-ordering and magnon collective modes for two-dimensional electron lattices in strong magnetic fields

R. Cote; A. H. MacDonald

doi:10.1103/physrevb.53.10019

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Spin-ordering and magnon collective modes for two-dimensional electron lattices in strong magnetic fields

R. Cote·A. H. MacDonald

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Abstract

We study the spin-ordering and the magnon collective modes of the two-dimensional Wigner crystal state at strong magnetic fields. Our work is based on the Hartree-Fock approximation for the ground state and the time-dependent Hartree-Fock approximation for the collective modes. We find that the ground state is ferromagnetic, i.e that all spins are aligned at T=0 even when the electronic g-factor is negligibly small. The magnon calculations show that the spin-stiffness is much smaller in the crystal state than in fluid states which occur at nearby Landau level filling factors.

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R. Cote, A. H. MacDonald. 1995-08-23. Spin-ordering and magnon collective modes for two-dimensional electron lattices in strong magnetic fields. https://doi.org/10.1103/physrevb.53.10019

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