Micro-reflectance and transmittance spectroscopy: a versatile and powerful tool to characterize 2D materials

Abstract

Optical spectroscopy techniques such as differential reflectance and transmittance have proven to be very powerful techniques to study 2D materials. However, a thorough description of the experimental setups needed to carry out these measurements is lacking in the literature. We describe a versatile optical microscope setup to carry out differential reflectance and transmittance spectroscopy in 2D materials with a lateral resolution of ~1 micron in the visible and near-infrared part of the spectrum. We demonstrate the potential of the presented setup to determine the number of layers of 2D materials and to characterize their fundamental optical properties such as excitonic resonances. We illustrate its performance by studying mechanically exfoliated and chemical vapor-deposited transition metal dichalcogenide samples.

5 main text figures + 1 table with all the part numbers to replicate the experimental setup + 4 supp. info. figures

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• Electric Field Effect in Atomically Thin Carbon Films
• The Raman Fingerprint of Graphene
• Anomalous Lattice Vibrations of Single and Few-Layer MoS2
• Valley polarization in MoS2 monolayers by optical pumping
• Making graphene visible
• Probing excitonic states in ultraclean suspended two-dimensional semiconductors by photocurrent spectroscopy
• Optical identification of atomically thin dichalcogenide crystals
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