Nomura Kentaro, MacDonald Allan H
Department of Physics, University of Texas at Austin, Austin, Texas 78712-1081, USA.
Phys Rev Lett. 2006 Jun 30;96(25):256602. doi: 10.1103/PhysRevLett.96.256602. Epub 2006 Jun 28.
Graphene is a two-dimensional carbon material with a honeycomb lattice and Dirac-like low-energy excitations. When Zeeman and spin-orbit interactions are neglected, its Landau levels are fourfold degenerate, explaining the 4e2/h separation between quantized Hall conductivity values seen in recent experiments. In this Letter we derive a criterion for the occurrence of interaction-driven quantum Hall effects near intermediate integer values of e2/h due to charge gaps in broken symmetry states.
石墨烯是一种具有蜂窝晶格和类狄拉克低能激发的二维碳材料。当忽略塞曼相互作用和自旋轨道相互作用时，其朗道能级是四重简并的，这解释了在最近实验中观察到的量子化霍尔电导率值之间4e²/h的间隔。在本信函中，我们推导了一个准则，用于说明由于对称性破缺态中的电荷能隙，在e²/h的中间整数值附近出现相互作用驱动的量子霍尔效应的情况。
