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Giant spin-dependent thermoelectric effect in magnetic tunnel junctions
Weiwei Lin1, Michel Hehn, Laurent Chaput
1Institut Jean Lamour, Nancy-Université, Boulevard des Aiguillettes, BP 239, Vandoeuvre-lès-Nancy 54506, France. weiwei.lin@u-psud.fr
Nature Communications
|March 22, 2012
Summary
Researchers observed a giant magnetothermoelectric effect in magnetic tunnel junctions, enabling spin caloritronics. This discovery allows tuning the Seebeck coefficient, advancing spintronic device applications in thermoelectricity.
Area of Science:
- Condensed Matter Physics
- Spintronics
- Nanotechnology
Background:
- Thermoelectric effects in magnetic nanostructures, known as spin caloritronics, are gaining significant attention.
- Spin currents are crucial for spin-based electronics, offering novel control and manipulation methods.
Purpose of the Study:
- To investigate and report a giant magnetothermoelectric effect in a magnetic tunnel junction.
- To explore the potential of spintronic devices in thermoelectric applications.
Main Methods:
- Fabrication and characterization of magnetic tunnel junctions.
- Measurement of thermovoltage and Seebeck coefficient under varying magnetic configurations.
Main Results:
- A giant magnetothermoelectric effect was observed, with thermovoltages reaching 1 mV.
- A magnetothermovoltage effect comparable to the tunnel magnetoresistance ratio was measured.
- The Seebeck coefficient was found to be tunable by altering the relative magnetization orientation of the magnetic layers.
Conclusions:
- The study demonstrates the extension of spintronic device applications into thermoelectricity.
- The findings provide critical insights into the physics governing thermal spin transport.
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