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Thermal spin transfer in Fe-MgO-Fe tunnel junctions
Xingtao Jia1, Ke Xia, Gerrit E W Bauer
1Department of Physics, Beijing Normal University, Beijing 100875, China.
Physical Review Letters
|November 24, 2011
Summary
We calculated thermal spin transfer torques in iron-magnesium oxide-iron tunnel junctions. These torques can reverse magnetization with small temperature differences, potentially enabling high-frequency signal generation.
Area of Science:
- Condensed matter physics
- Materials science
- Spintronics
Background:
- Spintronic devices utilize electron spin for information processing.
- Thermal spin transfer (TST) torques offer a potential mechanism for manipulating magnetization.
Purpose of the Study:
- To compute TST torques in Fe-MgO-Fe tunnel junctions.
- To investigate the potential for magnetization reversal and high-frequency generation.
Main Methods:
- First-principles calculations.
- Wave-function-matching method.
- Modeling of Fe-MgO-Fe tunnel junctions.
Main Results:
- Calculated TST at room temperature for a junction with 3 MgO monolayers.
- Estimated magnetization reversal for temperature differences around 10 K.
- Identified multiple scattering between interface states as the cause for large TST.
- Observed skewed angular dependence of TST.
Conclusions:
- Fe-MgO-Fe tunnel junctions exhibit significant TST at room temperature.
- The observed TST can induce magnetization reversal and may lead to thermally induced high-frequency generation.
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