摘要
为了系统深入地研究MoS_2的电子能带结构和光电性质,基于密度泛函理论的第一性原理平面波赝势方法,计算和分析了材料MoS_2的电子结构及其光学性质,给出了MoS_2的能带结构、光吸收谱、电子态密度、能量损失谱、反射谱、介电函数谱等光学性质。计算结果表明:体材料MoS_2的电子跃迁形式是非垂直跃迁,具有间接带隙的半导体材料,带隙宽为1.126 eV;价带和导带的形成是由Mo和S的价电子起作用产生的。通过分析其光学性质,发现MoS_2的介电函数的实部和虚部的峰值都出现在低能区,当光子能量的升高,介电函数值会缓慢降低;材料MoS_2对可见紫外区域的光子具有很强的吸收,最大吸收系数为3.17×105cm^(-1);MoS_2在能量为18.33eV位置出现了共振现象,其它区域内能量的损失值都趋于为0,说明电子之间共振非常微弱。这些光学性质奠定了该材料在制作微电子和光电子器件方面的作用,尤其是在紫外探测器应用方面有着潜在的应用前景,为未来对MoS_2材料的进一步研究提供理论参考。
To study the electronic energy band structure and photoelectric properties of molybdenum disulfide( MoS2 )systematically,we use the first-principles plane wave pseudopotential method under the framework of density functional theory tocalculate and analyze the electronic structure of MoS2 and optical properties.The paper give the energy bandstructure,optical absorption spectrum,electron density,energy loss spectrum,reflection spectrum,and dielectric function spectrum.The calculation results show that the electronic transition form of the bulk material MoS2 is a non-vertical transition. MoS2 is a semiconductor material with an indirect bandgap which is equal to1.126eV.It is found that MoS2 has a strong absorption of visible photons in the ultraviolet region with a maximum absorption coefficient of3.17×10^5cm^-1. MoS2 has a resonance phenomenon at about18.33ev,and the energy loss value in other regions is0,which indicates that the resonance between electrons is very weak.The energy band structure of MoS2 lays a foundation for its role in the fabrication of microelectronics and optoelectronic devices,especially in the application of UV detectors with potential application prospects.
作者
范哲梅
蒋立鹏
伍冬兰
FAN Zhe-mei;JIANG Li-peng;WU Dong-lan(School of Mathematic and Physical, Jinggangshan University, Ji’an, Jiangxi 343009, China)
出处
《井冈山大学学报（自然科学版）》
2018年第6期7-13,共7页
Journal of Jinggangshan University (Natural Science)
基金
国家自然科学基金项目(11564019
11147158)
江西省教育厅科研课题(GJJ170654)
关键词
第一性原理
MOS2
电子结构
光学性质
first-principles
MoS2
electronic structure
optical properties
