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High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy
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Multiphoton Spectroscopy of a Dynamical Axion Insulator
Olivia Liebman1, Jonathan B Curtis1, Ioannis Petrides1
1University of California, College of Letters and Science, Los Angeles, California, USA.
Physical Review Letters
|November 21, 2025
Summary
We propose an all-optical method to detect axion quasiparticles in topological insulators. This technique uses pump-probe spectroscopy to observe axion field dynamics, aiding in identifying new quantum matter phases.
Area of Science:
- Condensed Matter Physics
- Quantum Materials
- Topological Insulators
Background:
- Magnetoelectric transport in Weyl semimetals and 3D topological insulators is linked to axion fields.
- Correlations can lead to emergent axion quasiparticles, exhibiting nonlinear coupling to electromagnetic fields.
- Identifying these collective axion modes is challenging due to their nonlinear dynamics.
Purpose of the Study:
- To propose an all-optical protocol for verifying and characterizing axion field dynamics.
- To investigate the transient behavior of axion fields in 3D insulator systems.
- To provide a method for identifying emergent axion quasiparticles.
Main Methods:
- Utilizing a pump-probe spectroscopy setup.
- Employing nonlinear Raman processes to induce axion field oscillations.
- Measuring material polarization and magnetization changes.
Main Results:
- Nonlinear Raman processes drive dynamical axion field oscillations dependent on electromagnetic field geometry.
- These oscillations are observable through changes in material polarization and magnetization.
- The proposed protocol enables detection via time-resolved Kerr rotation spectroscopy.
Conclusions:
- The study presents a viable all-optical method for detecting axion quasiparticles.
- This technique facilitates the characterization of axion field dynamics in quantum materials.
- Opens avenues for identifying novel correlated phases using multiphoton and quantum pair spectroscopies.
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