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Updated: Sep 12, 2025
10:17
20 mJ, 1 ps Yb:YAG Thin-disk Regenerative Amplifier
Published on: July 12, 2017
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Magnetic dynamics driven integer and fractional high harmonic generation arising from highly nonlinear instantaneous
1Université de Nouakchott, Avenue du Roi Faiçal, 2373, Nouakchott, Mauritania, Nouakchott, MAURITANIA.
Summary
We show that an adiabatic approach simplifies the study of magnetic dynamics-driven high harmonic generation (HHG). This method reveals key nonlinearities and predicts tunable harmonics, advancing ultrafast carrier dynamics research.
Area of Science:
- Condensed matter physics
- Ultrafast phenomena
- Nonlinear optics
Background:
- High harmonic generation (HHG) is a key process in nonlinear optics.
- Understanding the strongly nonlinear regime of magnetic dynamics-driven HHG is challenging.
- Current models often lack a simplified approach to capture complex dynamics.
Purpose of the Study:
- To develop a simplified theoretical framework for magnetic dynamics-driven HHG.
- To investigate the role of instantaneous energy dispersion in nonlinear HHG.
- To predict novel phenomena like tunable integer and fractional high harmonics.
Main Methods:
- Adiabatic treatment of magnetic dynamics.
- Analysis of instantaneous energy dispersion.
- Application to spin-orbit interaction and light-driven HHG.
Main Results:
- The adiabatic approach successfully captures the strongly nonlinear regime of HHG.
- A nonlinear term in the instantaneous energy dispersion mirrors high-frequency excitations.
- Tunable integer and fractional high harmonics are predicted with time-modulated spin-orbit interaction.
Conclusions:
- The instantaneous energy level dynamics offer a simplified understanding of HHG.
- This approach provides a new pathway for harnessing HHG in ultrafast carrier dynamics.
- Findings are applicable to both laser and precession-driven HHG phenomena.
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