Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
Phys Rev Lett. 2010 Dec 31;105(26):266405. doi: 10.1103/PhysRevLett.105.266405. Epub 2010 Dec 27.
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 S(j), we find a thermodynamic phase transition into an exotic spin ordering with uniform scalar spin chirality and (S(j))=0. The state exhibits a spontaneous quantum Hall effect. We also study how its properties are affected by the application of an external magnetic field.
我们通过结合零温变分方法和有限温蒙特卡罗模拟来研究三角格子上填充度为 1/4 的近藤晶格模型的行为。对于巡游电子和经典矩 S(j) 之间的中等耦合，我们发现会出现热力学相变，进入到具有均匀标量自旋手性和(S(j))=0 的奇特自旋有序相中。这个状态表现出自发量子霍尔效应。我们还研究了外加磁场对其性质的影响。
