Chemical Physics Letters ( IF 2.8 ) Pub Date : 2018-07-10 , DOI: 10.1016/j.cplett.2018.07.017 Junais Habeeb Mokkath
Using time dependent density functional theory (TDDFT) calculations, we investigate the impact of atomic defects on the band edge optical properties of MoS2 nanotubes. Our findings demonstrate the sensitivity of the optical properties of MoS2 nanotube to the details of the defect type. Transition density plot corresponding to the principal peak in the absorption spectrum allowed us to understand the differences in the band edge optical excitation of defected MoS2 nanotubes with respect to the pristine MoS2 nanotube. We found that pristine MoS2 nanotube supports collective plasmon-like excitation and this excitation can be strongly spatially localized depending on the defect type. More precisely, mono-carbon atom defect and/or sulfur vacancy defects favour strong degree of localization near the defected region. While in contrast, in the case of mono-silicon atom defect and/or molybdenum vacancy defects, the collective plasmon-like excitation of the MoS2 nanotube is only marginally affected. The strong degree of localization in combination with the entrance of in-gap states in the case of mono-carbon atom defect and/or sulfur vacancy defects could have wide implications in the field of transition metal dichalcogenides based nanodevices.
中文翻译:
变形的MoS 2纳米管的带边缘光学性质
使用基于时间的密度泛函理论(TDDFT)计算,我们研究了原子缺陷对MoS 2纳米管的带边光学性能的影响。我们的发现证明了MoS 2纳米管的光学特性对缺陷类型细节的敏感性。对应于吸收光谱中的主峰的跃迁密度图使我们能够了解缺陷的MoS 2纳米管相对于原始MoS 2纳米管的带边缘光激发的差异。我们发现原始的MoS 2纳米管支持集体等离激元样激发,并且该激发可以根据缺陷类型在空间上强烈定位。更精确地,单碳原子缺陷和/或硫空位缺陷有利于在缺陷区域附近的强烈的局部化程度。相反,在单硅原子缺陷和/或钼空位缺陷的情况下,MoS 2纳米管的集体等离激元样激发仅受到很小的影响。在单碳原子缺陷和/或硫空位缺陷的情况下,强烈的局域化程度与能隙状态的进入相结合,可能对基于过渡金属二卤化物的纳米器件领域产生广泛的影响。