硼磷烯量子点的电子结构和光学性质研究  

Study on electronic structure and optical properties of monolayerhexagonal boron phosphide quantum dots

作　　者：王乃晔 陈桥[1] WANG Nai-Ye;CHEN Qiao(School of Computing Science and Electronics,Hunan Institute of Engineering,Xiangtan 411104,China)

机构地区：[1]湖南工程学院计算科学与电子学院,湘潭411104

出　　处：《原子与分子物理学报》2024年第3期71-77,共7页Journal of Atomic and Molecular Physics

基　　金：湖南省自然科学基金(2022JJ424);湖南工程学院研究生科研创新项目(YC202216)。

摘　　要：采用紧束缚近似方法对锯齿状六边形硼磷烯量子点在平面电场和垂直磁场调控下的电子结构和光学性质进行了研究.研究表明,硼磷烯量子点作为直接带隙半导体,在无外加电场和磁场作用时,能隙不随尺寸的改变而变化.在平面电场调控下,能隙随电场强度的增加逐渐减小直至消失,平面电场方向几乎不会对硼磷烯量子点体系产生影响,且随量子点尺寸的增大,能隙消失所需电场强度逐渐减小.在垂直磁场调控下,表现为体态的能级在磁场作用下形成朗道能级,而能隙边缘处的朗道能级近似为一个平带,不随磁通量的改变而变化,态密度主要分布于朗道能级处.另外,垂直磁场作用下的光吸收主要是由朗道能级之间的跃迁引起的.The electronic structure and optical properties of monolayer hexagonal boron phosphide quantum dots with zigzag shape are studied by using tight binding method under planar electric and vertical magnetic fields. The results show that the energy gap of monolayer hexagonal boron phosphide quantum dots, as direct bandgap semiconductors, does not change with the size in the absence of electric or magnetic field. Under the control of the plane electric field, the energy gap gradually decreases with the increase of the electric field until it disappears. The direction of the plane electric field almost has no effect on the monolayer hexagonal boron phosphide quantum dots, and the strength of electric field required for the disappearance of the energy gap gradually decreases with the increase of the quantum dot size. Under the control of vertical magnetic field, the energy levels forms the Landau levels, while the Landau level at the edge of the energy gap is approximately a flat band, which does not change with the change of magnetic flux, and the density of states is mainly distributed at this Landau level. In addition, light absorption under vertical magnetic field is mainly caused by the transition between Landau levels.

关 键 词：硼磷烯 量子点 紧束缚近似方法 电子结构和光学性质 电场和磁场 

分 类 号：O64[理学—物理化学]