Abstract

Stacked 2D layers of materials exhibit unique electronic, optical, and magnetic properties. Changes in the stacking order of these materials can create different phases with novel properties. Tetralayer graphene has three possible stacking phases, where two of them were experimentally observed: the Bernal (ABAB) and Rhombohedral (ABCD)[1–3], while the elusive third ABCB/ABAC has proven much harder to detect (Figure 1 - A). In this work, we show that single wavelength (0.63 eV) Scattering Scanning Near-field Optical Microscopy (S-SNOM), in combination with an Oscillating Spherical Dipole (OSD) model, can be used to clearly image and categorize all three phases of tetralayer graphene.

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