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Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
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Light-induced electronic polarization in antiferromagnetic Cr2O3
Xinshu Zhang1, Tyler Carbin1, Adrian B Culver1,2
1Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, CA, USA.
Nature Materials
|April 1, 2024
Summary
Researchers used light pulses to break electronic symmetries in chromium oxide (Cr2O3). This purely electronic response creates a controllable dipole moment, opening doors for novel solid-state phenomena.
Area of Science:
- Solid-state physics
- Quantum materials
- Nonlinear optics
Background:
- Electronic subsystems in solids can display order with symmetry lower than the crystal lattice.
- Investigating ultrafast external fields coupling to electronic order parameters is crucial for exotic effects.
Purpose of the Study:
- To demonstrate symmetry breaking in solids using ultrafast optical fields.
- To explore the induction of exotic electronic effects via optical rectification.
Main Methods:
- Utilized linearly polarized light pulses transmitted through chromium oxide (Cr2O3).
- Employed interferometric time-resolved second harmonic generation to probe symmetry changes.
- Investigated the role of broken inversion symmetry due to antiferromagnetic order.
Main Results:
- Observed in-plane rotational symmetry breaking (C3 to C1) via optical rectification.
- Confirmed the ultrafast, purely electronic nature of the response, leaving spin and crystal structures intact.
- Demonstrated the creation of a dipole moment in the symmetry-broken state with controllable polar axis.
Conclusions:
- Established a nonlinear optical protocol for coherently breaking electronic symmetries in solids.
- Showcased a method to generate unconventional electronic effects by controlling electronic symmetry.
- Highlighted the potential of light-matter interactions for manipulating electronic properties.
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