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Updated: Aug 15, 2025
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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
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Polarization-resolved and helicity-resolved Raman spectra of monolayer XP3 (X = Ge and In)
Haiming Huang1,2, Huijun Liu2, Mingquan Ding1,2
1Research Center for Advanced Information Materials (CAIM), Huangpu Research and Graduate School of Guangzhou University, Guangzhou 510555, China. slzhang@gzhu.edu.cn.
Physical Chemistry Chemical Physics : PCCP
|January 4, 2023
Summary
Monolayer Germanium Phosphide (GeP3) and Indium Phosphide (InP3) exhibit distinct Raman properties due to their unique symmetries. This study reveals their optical characteristics for advanced electronic and optoelectronic applications.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Two-dimensional (2D) materials offer unique electronic and optical properties.
- Monolayer XP3 (X = Ge, In) are theoretically predicted 2D materials with potential in photovoltaics and optoelectronics.
- Understanding their optical properties is crucial for application development.
Purpose of the Study:
- To systematically investigate the polarization-resolved and helicity-resolved Raman spectra of monolayer GeP3 and InP3.
- To elucidate the relationship between symmetry, Raman activity, and optical properties.
- To guide the design and application of these 2D materials.
Main Methods:
- Density functional theory (DFT) calculations.
- Phonon dispersion analysis for dynamical stability.
- Systematic investigation of Raman spectra excited by 532 nm and 633 nm laser lines.
- Analysis of polarization-resolved and helicity-resolved Raman spectra.
Main Results:
- Monolayer GeP3 and InP3 possess different point group symmetries and Raman properties.
- Raman anisotropy was observed, with phonons categorized by polarization-dependent intensity maxima.
- Helicity-resolved spectra showed a strong helicity selection rule under normal helical excitation.
- Dynamical stability confirmed via phonon dispersion.
Conclusions:
- The distinct Raman signatures of monolayer GeP3 and InP3 arise from their differing symmetries.
- The study provides a comprehensive understanding of their optical properties and Raman anisotropy.
- These findings facilitate the targeted design and characterization of XP3 for electronics and optoelectronics.
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