Partial Disorder on a Triangular Lattice

Abstract

AbstractIn this chapter, we study magnetic and electronic properties of an Ising-spin Kondo lattice model on a triangular lattice. We present that the model shows rich phase diagram with various magnetic phases: two-sublattice stripe, three-sublattice ferrimganetic, and partially disordered states. In addition to these long-range orders, we also found a Kosterlitz-Thouless like quasi-long-range order. In these four states, partial disorder and Kosterlitz-Thouless like states are thermally-induced phases that only apears in intermediate temperature region above other long-range orders. Interestingly, the partially disordered phase is insulating and show charge disproportionation. We also present analysis of a mean-field calculation of the band structure and discuss that the partial disorder in the present model is potentially stabilized by the charge gap formation.Keywords Partial disorderGeometrical frustrationBerezinskii-Kosterlitz-Thouless transition