Complex Raman Tensor in Helicity-Changing Raman Spectra of Black Phosphorus under Circularly Polarized Light
Journal
Journal of Physical Chemistry Letters
Journal Volume
13
Journal Issue
5
Start Page
1241
End Page
1248
ISSN
19487185
Date Issued
2022
Author(s)
Abstract
In anisotropic two-dimensional materials, complex values of Raman tensors are necessary to explain the abnormal linearly polarized Raman spectra. In this work, we measured the helicity-changing Raman spectra of few-layer black phosphorus (BP) excited by circularly polarized light. We observed that the polarized Raman intensities of the Ag modes show a deflection angle that depends on the sample orientation, thickness, and laser excitation energy. To understand the deflection, we calculated the resonant Raman spectra by first-principles calculations, which give complex Raman tensors as a function of laser excitation energy. In particular, the phase difference between the elements of the complex Raman tensor is relevant to the deflection angle. The calculated results of monolayer BP reproduce the experimental helicity-resolved Raman spectra of few-layer BP satisfactorily.
Subjects
Calculations
Circular Polarization
Light Polarization
Phosphorus
Raman Scattering
Tensors
Circularly Polarized Light
Complex Values
Deflection Angles
Helicities
Linearly Polarized
Polarized Raman
Polarized Raman Spectra
Raman Intensities
Raman Tensor
Two-dimensional Materials
Laser Excitation
Publisher
American Chemical Society
Type
journal article