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Updated: Apr 24, 2026
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High-Temperature and High-Pressure In situ Magic Angle Spinning Nuclear Magnetic Resonance Spectroscopy
Published on: October 9, 2020
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High-harmonic spin and charge pumping in altermagnets.
1Université de Nouakchott, Faculté des Sciences et Techniques, Département de Physique, Avenue du Roi Faiçal, 2373 Nouakchott, Mauritania.
Summary
Altermagnets exhibit highly nonlinear spin and charge pumping due to inherent spin-momentum coupling. This enables efficient THz emitters and advanced spintronic devices without extra spin-orbit coupling.
Area of Science:
- Condensed Matter Physics
- Spintronics
- Materials Science
Background:
- Altermagnetic systems possess unique non-relativistic spin-momentum coupling.
- This coupling leads to momentum-dependent spin splitting, crucial for spin dynamics.
- Conventional ferromagnets and antiferromagnets often require additional spin-orbit coupling for nonlinear effects.
Purpose of the Study:
- To investigate nonlinear spin and charge pumping in altermagnetic systems.
- To explore the potential of altermagnets for generating high harmonics.
- To assess altermagnets as platforms for THz emitters and spintronic devices.
Main Methods:
- Theoretical modeling and numerical simulations of altermagnetic systems.
- Analysis of spin-flip scattering driven by precessing magnetic order.
- Investigation of harmonic generation under realistic conditions.
Main Results:
- Observed emergence of highly nonlinear spin and charge pumping.
- Demonstrated intrinsic high-harmonic generation in altermagnets, surpassing light-driven schemes.
- Simulations revealed emission of hundreds of harmonics with large amplitudes.
Conclusions:
- Altermagnets intrinsically support high-harmonic spin and charge pumping.
- These systems offer a promising route to efficient THz emitters.
- Altermagnetic materials are ideal for developing highly nonlinear spintronic devices.
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