基于锗烯的铁磁范德华异质结构中的谷依赖多量子态与拓扑相变
Valley-dependent Multiple Quantum States and Topological Transitions in Germanene-based Ferromagnetic van der Waals Heterostructures
AI总结：
基于第一性原理计算，发现锗烯铁磁异质结构可实现多种谷依赖量子态（如QAHE、QVHE等），并通过磁场调控磁取向实现拓扑相变，为电子学与自旋电子学提供新材料平台。
摘要：
拓扑和谷电子材料因其独特的性质在自旋电子学和量子应用中具有广阔前景。通过第一性原理计算，我们证明了基于锗烯（Ge）的铁磁异质结构可以展现多种量子态，如陈数为C=-1或C=-2的量子反常霍尔效应（QAHE）、谷陈数为C_v=2的量子谷霍尔效应（QVHE）、具有两个陈数C=-1和C_v=-1的谷极化量子反常霍尔效应（VP-QAHE），以及自旋陈数为C_s~1的时间反演对称性破缺的量子自旋霍尔效应（T-broken QSHE）。此外，我们发现通过施加磁场改变铁磁层的磁取向，可以实现不同量子态之间的转变。我们的发现为电子学、自旋电子学和谷电子学中的应用提供了具有多种特性独特组合的新路径和新材料平台。
英文摘要：
Topological and valleytronic materials are promising for spintronic and quantum applications due to their unique properties. Using first principles calculations, we demonstrate that germanene (Ge)-based ferromagnetic heterostructures can exhibit multiple quantum states such as quantum anomalous Hall effect (QAHE) with Chern numbers of C=-1 or C=-2, quantum valley Hall effect (QVHE) with a valley Chern number of C$v$=2, valley-polarized quantum anomalous Hall effect (VP-QAHE) with two Chern numbers of C=-1 and C$v$=-1 as well as time-reversal symmetry broken quantum spin Hall effect (T-broken QSHE) with a spin Chern number of C$s$~1. Furthermore, we find that the transitions between different quantum states can occur by changing the magnetic orientation of ferromagnetic layers through applying a magnetic field. Our discovery provides new routes and novel material platforms with a unique combination of diverse properties that make it well suitable for applications in electronics, spintronics and valley electronics.
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。
