Non-Degenerate Ground State in the Antiferromagnetic Double-Exchange Model on a Triangular Lattice

Yoshihiro Shimomura; Shin Miyahara; Nobuo Furukawa

doi:10.1016/j.stam.2005.11.014

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Non-Degenerate Ground State in the Antiferromagnetic Double-Exchange Model on a Triangular Lattice

Yoshihiro Shimomura·Shin Miyahara·Nobuo Furukawa

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Abstract

In order to study effects of frustration in an itinerant electron system, we investigate ground states of the antiferromagnetic double-exchange model on a triangular lattice. In this model, pseudo-spins are coupled to electron transfer integrals in such a way that antiparallel configurations of pseudo-spins gain kinetic energies. Although the antiferromagnetic Ising model on a triangular lattice shows macroscopic dengenerate ground states, the present model shows that the degeneracy is lifted due to long-range natures of the double exchange interactions. Spin ordering at the ground state is also discussed.

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Yoshihiro Shimomura, Shin Miyahara, Nobuo Furukawa. 2005-05-18. Non-Degenerate Ground State in the Antiferromagnetic Double-Exchange Model on a Triangular Lattice. https://doi.org/10.1016/j.stam.2005.11.014

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