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Updated: Jun 10, 2025
10:40
High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy
Published on: June 28, 2016
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Phonon-Induced Geometric Chirality.
Carl P Romao1, Dominik M Juraschek2
1Department of Materials, ETH Zurich, CH-8093 Zurich, Switzerland.
ACS Nano
|October 18, 2024
Summary
Researchers demonstrate inducing chirality in achiral crystals using geometric chiral phonons and laser pulses. This breakthrough allows on-demand control over material chirality, enabling new chiral electronic and optical properties.
Area of Science:
- Condensed matter physics
- Quantum optics
- Materials science
Background:
- Chiral properties are increasingly vital in quantum optics, plasmonics, and phononics.
- Controlling material chirality on demand remains a significant challenge in these fields.
Purpose of the Study:
- To demonstrate the induction of geometric chirality in achiral crystals using phonons.
- To enable on-demand control over material chirality for engineering novel properties.
Main Methods:
- Excitation of achiral crystals with ultrashort laser pulses.
- Utilizing linearly polarized phonons to induce structural asymmetry.
- Leveraging nonlinear phonon coupling to displace crystal structures.
Main Results:
- Achiral crystals were successfully induced with geometric chirality.
- Selective induction of two enantiomers was achieved by reorienting laser polarization.
- Phonon-induced symmetry reduction to chiral point groups was observed.
Conclusions:
- Geometric chiral phonons offer a novel method for light-induced chirality in materials.
- This technique enables the engineering of chiral electronic states and optical properties.
- On-demand control over material chirality is now achievable.
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