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Spin current driven by ultrafast magnetization of FeRh
Kyuhwe Kang1, Hiroki Omura2, Daniel Yesudas1
1Department of Energy Science, Sungkyunkwan University, Suwon, 16419, Korea.
Nature Communications
|June 29, 2023
Summary
Researchers experimentally probed ultrafast spin currents during laser-induced magnetization of FeRh. Findings reveal spin currents are crucial for angular momentum buildup, not just dissipation.
Area of Science:
- Condensed Matter Physics
- Ultrafast Magnetism
- Spintronics
Background:
- Laser-induced demagnetization studies angular momentum dynamics in solids.
- The role of electron-carried spin currents in demagnetization is debated.
- Ultrafast magnetization is the inverse process, involving angular momentum buildup.
Purpose of the Study:
- To experimentally investigate the spin current during laser-induced ultrafast magnetization of FeRh.
- To understand the origin and role of spin currents in angular momentum buildup.
- To correlate spin current dynamics with magnetization dynamics in FeRh/Cu heterostructures.
Main Methods:
- Time-resolved magneto-optical Kerr effect measurements.
- Utilizing FeRh/Cu heterostructures to study spin current.
- Analyzing the correlation between spin current and magnetization dynamics.
Main Results:
- Direct measurement of ultrafast-magnetization-driven spin current in FeRh/Cu.
- Strong correlation observed between spin current and FeRh magnetization dynamics.
- Negligible spin filter effect observed in this inverse process.
Conclusions:
- Angular momentum buildup involves transfer from electron to magnon bath.
- Spin current facilitates spatial transport of angular momentum.
- Dissipation to the phonon bath occurs via spin relaxation.
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