Raman Characterization of Graphene and 2D TMD Heterostructures

We report efforts to produce and characterize graphene and two-dimensional transition-metal dichalcogenides (TMD) heterostructures. Using PDMS stamps, exfoliation of graphene, MoS$_{2}$, h-BN, and TaS$_{2}$ precedes the stacking of these mono- and few layers into heterostructures. The goal is to engineer mis-orientation to enhanced Raman signatures of various layers within the heterostructures. Previous studies have reported a Raman signal strength that is angle dependent between bi-layers [1]. Using resonant Raman spectroscopy, we probe the quality of these constructed heterostructures. Ultimately, we plan to combine our optical measurements with an applied magnetic field to probe the complex magneto-Raman interaction. Previous studies [2] show a magneto-phonon resonance at specific field strengths and laser excitations. Our results to date will be summarized.\\[4pt] [1] K. Kwanpyo \textit{et al. }Phys. Rev. Lett. \textbf{108}, 246103 (2012)\\[0pt] [2] C. Qiu \textit{et. al. }Phys. Rev. Lett. \textbf{88, }165407 (2013)