Spin-torque oscillator using a perpendicular polarizer and a planar free layer.
Spintronics materials have recently been considered for radio-frequency devices such as oscillators by exploiting the transfer of spin angular momentum between a spin-polarized electrical current and the magnetic nanostructure it passes through. While previous spin-transfer oscillators (STOs) were based on in-plane magnetized structures, here we present the realization of an STO that contains a perpendicular spin current polarizer combined with an in-plane magnetized free layer. This device is characterized by high-frequency oscillations of the free-layer magnetization, consistent with out-of-plane steady-state precessions induced at the threshold current by a spin-transfer torque from perpendicularly polarized electrons. The results are summarized in static and dynamic current-field state diagrams and will be of importance for the design of STOs with enhanced output signals.
Houssameddine
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D
SPINTEC URA 2512, C.E.A/DRFMC-CNRS, Commissariat á l'Energie Atomique-Grenoble, 17 rue des Martyrs, 38054 Grenoble, France.
Ebels
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U
Delaët
B
B
Rodmacq
B
B
Firastrau
I
I
Ponthenier
F
F
Brunet
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M
Thirion
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C
Michel
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JP
Prejbeanu-Buda
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L
Cyrille
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MC
Redon
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O
Dieny
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B