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Spin-torque oscillator using a perpendicular polarizer and a planar free layer.
D Houssameddine1, U Ebels, B Delaët
1SPINTEC URA 2512, C.E.A/DRFMC-CNRS, Commissariat á l'Energie Atomique-Grenoble, 17 rue des Martyrs, 38054 Grenoble, France.
Nature Materials
|May 1, 2007
Summary
This study introduces a novel spin-transfer oscillator (STO) using a perpendicular polarizer and in-plane free layer. This design enables high-frequency oscillations for advanced radio-frequency devices.
Area of Science:
- Spintronics
- Materials Science
- Radio-Frequency Devices
Background:
- Spintronics materials are explored for radio-frequency oscillators.
- Spin-transfer oscillators (STOs) typically use in-plane magnetized structures.
Purpose of the Study:
- To realize a novel STO design combining a perpendicular spin current polarizer with an in-plane magnetized free layer.
- To investigate the high-frequency oscillation characteristics of this new STO configuration.
Main Methods:
- Fabrication of an STO device with a perpendicular spin current polarizer and an in-plane magnetized free layer.
- Characterization of device performance through static and dynamic current-field state diagrams.
Main Results:
- The device exhibits high-frequency oscillations of the free-layer magnetization.
- Observed oscillations are consistent with out-of-plane steady-state precessions induced by spin-transfer torque from perpendicularly polarized electrons.
- Threshold current for oscillations was determined.
Conclusions:
- The novel STO design successfully generates high-frequency oscillations.
- This configuration is important for designing STOs with improved output signals.
- The findings advance the development of spintronic radio-frequency devices.
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