标题： 倾斜角和压力对单层晶体在密排钻石表面振动响应的依赖性 显示英文标题

标题： Orientation- and pressure-dependence of the vibrational response of a monolayer crystal on a vicinal diamond surface

摘要： 我们系统地研究了单层WS₂晶体在金刚石的(100)和(230)表面上的偏振依赖拉曼光谱。在常压下，在不同的表面观察到相同的拉曼光谱偏振依赖性，这与单层晶体相对于金刚石晶体的取向无关。然而，当单层WS₂被压缩至约4 GPa时，在(100)表面以及沿(230)表面原子台阶边缘的锯齿方向上，2LA模相对于A'模的强度突然下降。相比之下，当锯齿方向沿着或与(230)表面的原子台阶呈15{\deg }时，没有观察到这种下降。我们还观察到在压缩过程中，(230)表面上2LA模和A'模强度最大值的偏振角发生了偏移。这些结果表明，斜面表面上的原子台阶在高压下强烈改变了振动响应。 显示英文摘要

摘要： We systematically investigate polarization-dependent Raman spectra of a monolayer crystal of WS2 on the (100) and (230) surfaces of diamond. At ambient pressure, identical polarization dependence of the Raman spectra is observed on the different surfaces, independent of the orientation of the monolayer crystal relative to the diamond crystal. However, when monolayer WS2 is compressed to about 4 GPa, an abrupt drop of the intensity of the 2LA mode relative to the A' mode occurs on the (100) surface and the (230) surface with the zigzag direction along the atomic step edges of the (230) surface. In contrast, no such drop is observed when the armchair direction is along or at 15{\deg} to the atomic steps of the (230) surface. We also observe a shift of the polarization angle of the intensity maxima of the 2LA and A' modes on (230) surface during compression. These results demonstrate that the atomic steps of a vicinal surface strongly modify the vibrational response under high pressure.