This study presents a method based on the total internal reflection and phase-shifting interferometry for measuring the Van Hove singularities in strained graphene. A linearly polarized light passes through some quarter- and half-wave plates, a hemi-cylindrical prism, and a Mach-Zehnder interferometer. The Van Hove singularities manifest themselves as some sharp dips or peaks in the spectrum of the final phase difference of the two interference signals. The numerical analysis demonstrates that the number of Van Hove singularities is independent of the modulus of the applied stress, but their position shifts as the strength of the tension increases. Moreover, the number and location of singularities strongly depend on the stress direction relative to the zigzag axis in the graphene lattice. We also show that the location of singularities is independent of the tension direction relative to the tangential component of the electric field of the incident radiation. (C) 2020 Optical Society of America
展开▼
机译:该研究提出了一种基于全内反射和移相干涉测量法的方法,用于测量应变石墨烯的van Hove奇异性。线性偏振光通过一些四分之一和半波形板,半圆柱棱镜和马赫Zehnder干涉仪。 van Hove奇点在两个干扰信号的最终相位差的光谱中表现为一些尖锐的倾角或峰值。数值分析表明,范索彼此奇点的数量与施加应力的模量无关,但它们的位置随着张力强度的增加而变化。此外,奇点的数量和位置非常依赖于石墨烯晶格中相对于Z字形轴的应力方向。我们还表明,奇点的位置与相对于入射辐射的电场的切向分量相对于张紧组件无关。 (c)2020美国光学学会
展开▼