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Phonon Pseudoangular Momentum in α-MoO3
Meiqi Li1, Zhibing Li2,3,4, Huanjun Chen3,4,5
1School of Physics, Sun Yat-sen University, Guangzhou 510275, China.
Nanomaterials (Basel, Switzerland)
|April 12, 2024
Summary
Phonons can carry pseudoangular momentum in two-fold screw rotational symmetry crystals like alpha-molybdenum trioxide (α-MoO3). This discovery guides circularly polarized Raman experiments and unlocks new applications.
Area of Science:
- Condensed matter physics
- Solid-state physics
- Phononics
Background:
- Recent studies reveal phonons can carry angular momentum, primarily in three-fold rotationally symmetric systems.
- Systems with two-fold screw rotational symmetry, like α-MoO3, lack exploration regarding phonon angular momentum.
Purpose of the Study:
- To investigate pseudoangular momentum of phonons in crystals exhibiting two-fold screw rotational symmetry.
- To elucidate selection rules for circularly polarized Raman spectroscopy based on pseudoangular momentum conservation in α-MoO3.
Main Methods:
- Theoretical investigation of phonon pseudoangular momentum.
- Analysis of selection rules in circularly polarized Raman scattering experiments.
- Case study using alpha-molybdenum trioxide (α-MoO3) as a representative material.
Main Results:
- Demonstrated the existence and properties of phonon pseudoangular momentum in two-fold screw symmetric crystals.
- Established clear selection rules for Raman experiments linked to pseudoangular momentum conservation.
- Identified α-MoO3 as a key material for studying these phenomena.
Conclusions:
- The study introduces pseudoangular momentum as a crucial property for phonons in two-fold screw symmetric systems.
- Provides experimental guidance for Raman spectroscopy, enabling the detection and manipulation of phonon pseudoangular momentum.
- Opens new avenues for utilizing phonon pseudoangular momentum in α-MoO3 for advanced applications.
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