Coupled spin-charge order in frustrated itinerant triangular magnets

Abstract

We uncover four new spin-charge ordered ground states in the strong coupling limit of the Kondo lattice model on triangular geometry. Two of the states at one-third electronic filling ($n=1/3$) consist of decorated ferromagnetic chains coupled antiferromagnetically with the neighboring chains. The third magnetic ground state is noncollinear, consisting of antiferromagnetic chains separated by a pair of canted ferromagnetic chains. An even more unusual magnetic ground state, a variant of the $120^{\circ }$ Yafet-Kittel phase, is discovered at $n=2/3$. These magnetic orders are stabilized by opening a gap in the electronic spectrum: a "band effect". All the phases support modulations in the electronic charge density due to the presence of magnetically inequivalent sites. In particular, the charge ordering pattern found at $n=2/3$ is observed in various triangular lattice systems, such as, 2H-AgNiO${}_2$, 3R-AgNiO${}_2$ and Na${}_x$CoO${}_2$.

5 pages, 4 figures

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Cited by in corpus (1)

• Vortices, skyrmions, and chirality waves in frustrated Mott insulators with a quenched periodic array of impurities