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Updated: May 23, 2026
06:42
Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
Local charge and spin currents in magnetothermal landscapes
Mathias Weiler1, Matthias Althammer, Franz D Czeschka
1Walther-Meißner-Institut, Bayerische Akademie der Wissenschaften, 85748 Garching, Germany.
Physical Review Letters
|April 3, 2012
Summary
Researchers used a laser to create thermal gradients in ferromagnetic films, studying charge and spin currents via the anomalous Nernst effect (ANE) and spin Seebeck effect (SSE). This enables local thermal spin/charge current generation and spin caloritronic imaging.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spintronics
Background:
- Ferromagnetic thin films are crucial for spintronic devices.
- Understanding thermal effects in magnetic materials is key for novel functionalities.
- Spin caloritronics explores the interplay of heat, charge, and spin currents.
Purpose of the Study:
- To investigate local charge and spin current generation in ferromagnetic films using laser-induced thermal gradients.
- To explore the anomalous Nernst effect (ANE) and spin Seebeck effect (SSE) at a local scale.
- To demonstrate spin caloritronic domain imaging capabilities.
Main Methods:
- Utilized a scannable laser beam to induce local thermal gradients in metallic (Co2FeAl) and insulating (Y3Fe5O12) ferromagnetic thin films.
- Measured local voltages arising from the anomalous Nernst effect in Co2FeAl.
- Detected local spin currents via the spin Seebeck effect and inverse spin Hall effect in an adjacent Pt layer on Y3Fe5O12.
Main Results:
- Successfully generated local charge currents via ANE in Co2FeAl thin films.
- Successfully generated local spin currents via SSE in Y3Fe5O12/Pt heterostructures.
- Demonstrated the capability for spin caloritronic imaging of magnetic domains.
Conclusions:
- Established a method for local thermal spin and charge current generation in ferromagnetic materials.
- Showcased the potential of spin caloritronics for advanced imaging techniques.
- Opened new avenues for nanoscale thermal and spin manipulation in magnetic systems.
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