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Updated: Jun 23, 2025
08:01
Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures
Published on: November 21, 2019
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Magnetic parity violation and parity-time-reversal-symmetric magnets
Hikaru Watanabe1, Youichi Yanase2
1Research Center for Advanced Science and Technology, University of Tokyo, Meguro-ku, Tokyo 153-8904, Japan.
Summary
Parity-time-reversal symmetry (PTsymmetry) is key in materials science. Odd-parity magnetic multipole order in centrosymmetric crystals reveals unique electronic properties and emergent responses.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Mechanics
Background:
- Parity-time-reversal symmetry (PTsymmetry) combines space inversion (P) and time reversal (T) operations.
- PTsymmetry is fundamental to material functionality and characterizes P and T symmetries.
- Odd-parity magnetic multipole order occurs in centrosymmetric crystals, preserving PT symmetry while breaking P and T symmetries.
Purpose of the Study:
- To review candidate materials exhibiting odd-parity magnetic multipole order.
- To overview the characteristic physical responses arising from this order.
- To explore emergent phenomena distinct from nonmagnetic P-symmetry breaking or ferromagnetic order.
Main Methods:
- Literature review of PT-symmetric systems.
- Analysis of theoretical frameworks for emergent responses.
- Identification of unusual electronic structures in relevant materials.
Main Results:
- PT-symmetric systems with odd-parity magnetic multipole order exhibit unique emergent responses.
- Off-diagonal and/or nonreciprocal responses are identified.
- These responses are linked to hidden spin-momentum locking and asymmetric band dispersion.
Conclusions:
- Odd-parity magnetic multipole order in PT-symmetric systems leads to novel physical phenomena.
- Understanding these responses is crucial for designing new materials with tailored electronic properties.
- The study highlights the importance of PTsymmetry in exploring exotic electronic states.
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