2010/06/30 by Yutaka Akagi, Yukitoshi Motome · 1 citation
Physics and Astronomy · #cond-mat.str-el
published as J. Phys. Soc. Jpn. 79, 083711 (2010) · 4 pages, 4 figures, accepted for publication in J. Phys. Soc. Jpn.; (v2) revised version including minor correction in Fig. 3 and addition of a reference
arxiv created 2010/07/02 · arxiv updated 2010/08/19
We investigate the ground-state phase diagram for the ferromagnetic Kondo lattice model on a triangular lattice by a variational calculation for various spin orderings up to a four-site unit cell. We find that a noncoplanar four-sublattice ordering with a finite scalar spin chirality emerges at and around 1/4 filling, in addition to the 3/4-filled case, which was predicted to be induced by the perfect nesting of the Fermi surface [I. Martin and C. D. Batista: Phys. Rev. Lett. \bf 101 (2008) 156402]. The 1/4-filling phase is stable in a wider range of parameters than the 3/4-filling one, and includes a large region of gapped insulating state characterized by a Chern number. We also compute the Hall conductivity in the chiral-ordered phases.