二维NiBr_(2)单层自旋电子输运以及光电性质

Spin transport characteristics and photoelectric properties of magnetic semiconductor NiBr_(2)monolayer

磁性半导体材料在自旋电子器件领域具有重要的应用前景.本文设计了一些基于磁性半导体NiBr_(2)单层的纳米器件结构,并采用密度泛函理论结合非平衡格林函数方法,研究了其自旋输运和光电性质.结果表明,在不同的输运方向(扶手椅形和锯齿形),NiBr_(2)单层PN结二极管表现出明显的整流效应及自旋过滤效应,这两种效应在其亚3 nm PIN结场效应晶体管中也同样存在.NiBr_(2)单层PIN结场效应晶体管的电子传输受到栅极电压的调控,电流随着栅极电压的增大受到抑制.另外,NiBr_(2)单层对蓝、绿光有较强的响应,其光电晶体管在两种可见光的照射下可以产生较强的光电流.本文研究结果揭示了NiBr_(2)单层的多功能特性,为镍基二卤化物在半导体自旋电子器件和光电器件领域的应用提供了重要参考.

Magnetic semiconductor materials have potential applications in spintronic devices.In this work,some nano-dev ice structures based on the magnetic semiconductor NiBr_(2) monolayer(NiBr_(2)-ML)are designed,their spin-resolved transport and photoelectric properties are studied by using density functional theory combined with non-equilibrium Green’s function method.The results show that both the NiBr_(2)-ML PN-junction diodes and sub-3 nanometer PIN-j unction field-effect transistors(FETs)exhibit the significant rectification and spin filtering effects in either the armchair or the zigzag direction.The gates can obviously tune the electron transmission of the PIN-j unction FETs.The current is significantly suppressed with the increase of gate voltage.In addition,NiBr_(2)-ML has a strong response to the blue and green light,thus its phototransistor can generate a strong photocurrent under the irradiation of blue and green light.The research results in this paper reveal the multifunctional characteristics of NiBr_(2)-ML,which provides an important reference for the application of nickelbased dihalides in semiconductor spintronic devices and optoelectronic devices.