Pakdel Fatemeh, Maleki Mohammad Ali
Department of Physics, University of Zanjan, University Blvd., Zanjan, 45371-38791, Iran.
Sci Rep. 2025 Aug 6;15(1):28795. doi: 10.1038/s41598-025-13840-4.
We explore the transport behavior of charge carriers in gapped bilayer graphene under a perpendicular magnetic field and electrostatic barriers. Using the Hamiltonian of the four low-energy bands of bilayer graphene, we compute the transmission probability and the associated conductance via the transfer matrix method. Our investigation reveals that altering the gap parameter (Δ), the energy (E), the number of magnetic barriers (N) and the magnetic field strength (B) changes the range of incident angles, resulting in a wave-vector filtering effect. These parameters also influence the forbidden zones of transmission and conductance in the magnetic system. A forbidden zone exists for [Formula: see text]. For a multibarrier structure with [Formula: see text], another forbidden zone appears for [Formula: see text], along with resonance effects and conductance oscillations as functions of N and E. A strong wave-vector filtering effect is observed for specific values of Δ and E. The Klein tunneling occurs for [Formula: see text] at low values of E and Δ. By focusing on the resonances in transmission and the oscillatory behavior of conductance with N, E and Δ, we can confine charge carriers within the studied magnetic bilayer graphene by efficiently adjusting these parameters. The perfect transmission is observed for appropriate values of the electrostatic barrier height and the widths of magnetic and non-magnetic regions. The conductance is suppressed when N, Δ or B exceed their critical values.
我们研究了带隙双层石墨烯在垂直磁场和静电势垒作用下电荷载流子的输运行为。利用双层石墨烯四个低能带的哈密顿量,通过转移矩阵法计算了传输概率和相关电导。我们的研究表明,改变能隙参数(Δ)、能量(E)、磁垒数量(N)和磁场强度(B)会改变入射角范围,从而产生波矢滤波效应。这些参数还会影响磁系统中传输和电导的禁带。对于[公式:见原文]存在一个禁带。对于具有[公式:见原文]的多势垒结构,对于[公式:见原文]会出现另一个禁带,同时还存在共振效应以及作为N和E函数的电导振荡。在特定的Δ和E值下观察到强波矢滤波效应。在低E和Δ值时,对于[公式:见原文]会发生克莱因隧穿。通过关注传输中的共振以及电导随N、E和Δ的振荡行为,我们可以通过有效调整这些参数将电荷载流子限制在所研究的磁性双层石墨烯内。对于静电势垒高度以及磁性和非磁性区域宽度的适当值,可以观察到完美传输。当N、Δ或B超过其临界值时,电导会受到抑制。