论文标题
WS $ _ {2} $单层中的Ultrafast Shift电流动力学
Ultrafast shift current dynamics in WS$_{2}$ monolayer
论文作者
论文摘要
在缺乏反转对称性的材料中，移位电流效应可能会使光伏的性能超过传统基于P-N连接的光伏的冲击式 - 标题极限。尽管已经通过二阶扰动理论研究了从第一原理研究的转移效应，但仍缺乏对热载体动力学的理解。我们通过实时传播时间依赖性密度功能理论（RT-TDDFT）研究了单层WS $ _ {2} $中移位电流的动力学。我们发现，打开灯光后，可以在10-20 fs之内生成移动电流，并在关闭灯光后大约几十秒钟内消散。该特性可用于超快光子检测。这项工作为理解转移效应的动态提供了重要的一步，这对于设备应用至关重要。
The shift current effect, in materials lacking inversion symmetry, may potentially allow the performance of photovoltaics to surpass the Shockley-Queisser limit for traditional p-n junction-based photovoltaics. Although the shift-current effect has been studied from first-principles via second-order perturbation theory, an understanding of the dynamics of hot carriers is still lacking. We investigate the dynamics of the shift current in monolayer WS$_{2}$ via real-time propagation time-dependent density functional theory (rt-TDDFT). We find that the shift current can be generated within 10 - 20 fs after turning on the lights and dissipates within approximately a few tens of femtoseconds after turning off the lights. This property can be used for ultrafast photon detection. This work provides an important step toward understanding the dynamics of shift-current effects, which is crucial for device applications.
