Stability of spontaneous quantum Hall state in the Triangular Kondo-lattice model

Understand

We study the behavior of the quarter-filled Kondo lattice model on a triangular lattice by combining a zero-temperature variational approach and finite-temperature Monte-Carlo simulations.

• For intermediate coupling between itinerant electrons and classical moments ${\bf S}_j$, we find a thermodynamic phase transition into an exotic spin ordering with uniform scalar spin chirality and $< {\bf S}_j >=0$.
• The state exhibits spontaneous quantum Hall effect.
• We also study how its properties are affected by application of an external magnetic field.