@article{2168b7b96ec849b680ca6779a9dd4a8a,
title = "Mid-Infrared Mapping of Four-Layer Graphene Polytypes Using Near-Field Microscopy",
abstract = "The mid-infrared (MIR) spectral region attracts attention for accurate chemical analysis using photonic devices. Few-layer graphene (FLG) polytypes are promising platforms, due to their broad absorption in this range and gate-tunable optical properties. Among these polytypes, the noncentrosymmetric ABCB/ACAB structure is particularly interesting, due to its intrinsic bandgap (8.8 meV) and internal polarization. In this study, we utilize scattering-scanning near-field microscopy to measure the optical response of all three tetralayer graphene polytypes in the 8.5-11.5 μm range. We employ a finite dipole model to compare these results to the calculated optical conductivity for each polytype obtained from a tight-binding model. Our findings reveal a significant discrepancy in the MIR optical conductivity response of graphene between the different polytypes than what the tight-binding model suggests. This observation implies an increased potential for utilizing the distinct tetralayer polytypes in photonic devices operating within the MIR range for chemical sensing and infrared imaging.",
keywords = "Bernal, Few-layer graphene, Mid-IR nano-imaging, Optical conductivity, Raman spectroscopy, Rhombohedral, Scanning near-field optical microscopy, Stacking order",
author = "Daniel Beitner and Shaked Amitay and {Salleh Atri}, Simon and Andrew McEllistrim and Tom Coen and Fal{\textquoteright}ko, {Vladimir I.} and Shachar Richter and {Ben Shalom}, Moshe and Haim Suchowski",
note = "Publisher Copyright: {\textcopyright} 2023 The Authors. Published by American Chemical Society",
year = "2023",
month = dec,
day = "13",
doi = "10.1021/acs.nanolett.3c02819",
language = "אנגלית",
volume = "23",
pages = "10758--10764",
journal = "Nano Letters",
issn = "1530-6984",
publisher = "American Chemical Society",
number = "23",
}