Valleytronics公司
密度泛函理论
线性二色性
材料科学
单层
凝聚态物理
偏振器
圆二色性
光子学
过渡金属
杰纳斯
结晶学
分子物理学
物理
光电子学
计算化学
纳米技术
光学
化学
双折射
铁磁性
自旋电子学
催化作用
生物化学
作者
Yağmur Aksu Korkmaz,Ceyhun Bulutay,Cem Sevik
标识
DOI:10.1021/acs.jpcc.1c00714
摘要
Semiconductor monolayer transition metal dichalcogenides (TMDs) have brought a new paradigm by introducing optically addressable valley degree of freedom. Concomitantly, their high flexibility constitutes a unique platform that links optics to mechanics via valleytronics. With the intention to expedite the research in this direction, we investigated ten TMDs, namely MoS2, MoSe2, MoTe2, WS2, WSe2, WTe2, MoSSe, MoSeTe, WSSe, and WSeTe, which particularly includes their so-called janus types (JTMDs). First, we obtained their electronic band structures using regular and hybrid density functional theory (DFT) calculations in the presence of the spin–orbit coupling and biaxial or uniaxial strain. Our DFT results indicated that against the expectations based on their reported piezoelectric behavior, JTMDs typically interpolated between the standard band properties of the constituent TMDs without producing a novel feature. Next, by fitting to our DFT data we generated both spinless and spinful k · p parameter sets which are quite accurate over the K valley where the optical activity occurs. As an important application of this parametrization, we considered the circular and linear dichroism under strain. Among the studied (J)TMDs, WTe2 stood out with its largest linear dichroism under uniaxial strain because of its narrower band gap and large K valley uniaxial deformation potential. This led us to suggest WTe2 monolayer membranes for optical polarization-based strain measurements, or conversely, as strain tunable optical polarizers.
科研通智能强力驱动
Strongly Powered by AbleSci AI