Deep-Ultraviolet and Helicity-Dependent Raman Spectroscopy for Carbon Nanotubes and 2D Materials
Journal
Small
Journal Volume
21
Journal Issue
28
Start Page
2308558
ISSN
16136829
16136810
Date Issued
2025
Author(s)
Saito, Riichiro
Yang, Teng
Huang, Jianqi
Liu, Hsianglin
Gulo, Desman Perdamaian
Han, Shiyi
Tong, Lianming
Abstract
Recent progress of Raman spectroscopy on carbon nanotubes and 2D materials is reviewed as a topical review. The Raman tensor with complex values is related to the chiral 1D/2D materials without mirror symmetry for the mirror in the propagating direction of light, such as chiral carbon nanotube and black phosphorus. The phenomenon of complex Raman tensor is observed by the asymmetric polar plot of helicity-dependent Raman spectroscopy using incident circularly-polarized lights. First-principles calculations of resonant Raman spectra directly give the complex Raman tensor that explains helicity-dependent Raman spectra and laser-energy-dependent relative intensities of Raman spectra. In deep-ultraviolet (DUV) Raman spectroscopy with 266 nm laser, since the energy of the photon is large compared with the energy gap, the first-order and double resonant Raman processes occur in general k points in the Brillouin zone. First-principles calculation is necessary to understand the DUV Raman spectra and the origin of double-resonance Raman spectra. Asymmetric line shapes appear for the G band of graphene for 266 nm laser and in-plane Raman mode of WS2 for 532 nm laser, while these spectra show symmetric line shapes for other laser excitation. The interference effect on the asymmetric line shape is discussed by fitting the spectra to the Breit–Wigner–Fano line?shapes.
Subjects
Deep-ultraviolet Raman Spectroscopy
Helicity-dependent Raman Spectra
Tip-enhanced Raman Spectroscopy
Phosphorus
Incident Light
Laser Excitation
Mirrors
Raman Scattering
Raman Spectroscopy
Tensors
Tungsten Compounds
Deep Ultraviolet
Deep-ultraviolet Raman Spectroscopy
First Principle Calculations
Helicities
Helicity-dependent Raman Spectrum
Lines Shapes
Raman Tensor
Resonant Raman
Spectra's
Tip-enhanced Raman Spectroscopy
Carbon Nanotubes
Carbon Nanotube
Graphene
Phosphorus
Controlled Study
Drug Toxicity
Laser
Photon
Raman Spectrometry
Review
Ultraviolet Radiation
Publisher
John Wiley and Sons Inc
Type
review article