论文标题
通过在双螺旋剪上的水分子吸收引起的铁电性
Ferroelectricity induced by the absorption of water molecules on double helix SnIP
论文作者
论文摘要
我们研究了由带有吸收水分子的双螺旋片组成的一维系统中的铁电性。我们的从头算计算揭示了两个对电偏振至关重要的因素。第一个是在sinip的R2区域停留的极化水分子的方向。第二个是I原子的位移，它源于与吸收水分子的微妙相互作用。这项研究提出了一个合理的极化翻转场景。在这种情况下，水分子正在滚动，以保持其电偶极子的大小并改变方向，同时，I原子的位移也被逆转。高度可调节的极化可以通过施加应变来实现，通过施加拉伸应变的26.5％的极化增强，只有4％的压缩应变观察到4％降解。最后，还发现直接带隙与应变相关。
We study the ferroelectricity in a one-dimensional system composed of a double helix SnIP with absorbing water molecules. Our ab initio calculations reveal two factors that are critical to the electrical polarization. The first one is the orientation of polarized water molecules staying in the R2 region of SnIP. The second one is the displacement of I atom which roots from subtle interaction with absorbed water molecules. A reasonable scenario of polarization flipping is proposed in this study. In the scenario, the water molecule is rolling-up with keeping the magnitude of its electrical dipole and changing its direction, meanwhile, the displacement of I atoms is also reversed. Highly tunable polarization can be achieved by applying strain, with 26.5% of polarization enhancement by applying tensile strain, with only 4% degradation is observed with 4% compressive strain. Finally, the direct band gap is also found to be correlated with strain.
