石墨烯在$ν=0$上从量子霍尔金属到量子霍尔绝缘体的拓扑转变
Topological Transition of Graphene from Quantum Hall Metal to Quantum Hall Insulator at $ν=0$
摘要：
研究了在强磁场量子霍尔（QH）实验中填充因子为$ν=0$的石墨烯绝缘相的问题。结果表明，磁场驱动的Peierls型晶格畸变（由于朗道能级简并）和随机键涨落相互竞争，导致在$ν=0$下从相对低场的QH-金属态到足够高场的QH-绝缘体态的跃迁.分离QH-金属和QH-绝缘体的临界场取决于键涨落。该图很好地解释了为什么对于更清洁的样品，观察绝缘相所需的场更低。
英文摘要：
The puzzle of recently observed insulating phase of graphene at filling factor $ν=0$ in high magnetic field quantum Hall (QH) experiments is investigated. We show that the magnetic field driven Peierls-type lattice distortion (due to the Landau level degeneracy) and random bond fluctuations compete with each other, resulting in a transition from a QH-metal state at relative low field to a QH-insulator state at high enough field at $ν=0$. The critical field that separates QH-metal from QH-insulator depends on the bond fluctuation. The picture explains well why the field required for observing the insulating phase is lower for a cleaner sample.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
