Wojciechowska I, Dyrdał A
Faculty of Physics and Astronomy, ISQI, Adam Mickiewicz University in Poznań, ul. Uniwersytetu Poznańskiego 2, 61-614, Poznań, Poland.
Sci Rep. 2024 Oct 11;14(1):23808. doi: 10.1038/s41598-024-74596-x.
We consider the anomalous, spin, valley, and valley spin Hall effects in a pristine graphene-based van-der-Waals (vdW) heterostructure consisting of a bilayer graphene (BLG) sandwiched between a semiconducting van-der-Waals material with strong spin-orbit coupling (e.g., ) and a ferromagnetic insulating vdW material (e.g. ). Due to the exchange proximity effect from one side and spin-orbit proximity effect from the other side of graphene, such a structure is referred to as graphene based 'ex-so-tic' structure. First, we derive an effective Hamiltonian describing the low-energy states of the structure. Then, using the Green's function formalism, we obtain analytical results for the Hall conductivities as a function of the Fermi energy and gate voltage. For specific values of these parameters, we find a quantized valley Hall conductivity.
我们研究了一种由双层石墨烯（BLG）夹在具有强自旋轨道耦合的半导体范德华材料（例如 ）和铁磁绝缘范德华材料（例如 ）之间组成的原始石墨烯基范德华（vdW）异质结构中的反常、自旋、谷和谷自旋霍尔效应。由于石墨烯一侧的交换近邻效应和另一侧的自旋轨道近邻效应，这种结构被称为基于石墨烯的“奇特”结构。首先，我们推导了一个描述该结构低能态的有效哈密顿量。然后，使用格林函数形式，我们得到了作为费米能量和栅极电压函数的霍尔电导率的解析结果。对于这些参数的特定值，我们发现了量子化的谷霍尔电导率。
