Nonuniformity of a planar polarizer for spin-transfer-induced vortex oscillations at zero field

Applied Physics Letters

Volumn 96, Issue 21, 2010, Pages

  Khvalkovskiy, A V ^a,b   Grollier, J ^a   Locatelli, N ^a   Gorbunov, Ya V ^b   Zvezdin, K A ^b,c   Cros, V ^a  

^a UNITÉ MIXTE DE PHYSIQUE CNRS THALES   (France)

^b PROKHOROV GENERAL PHYSICS INSTITUTE   (Russian Federation)

^c Istituto PM Srl   (Italy)

Author keywords

[No Author keywords available]

Indexed keywords

EXCITATION EFFICIENCY; FREE LAYERS; LARGE AMPLITUDE; MAGNETIZATION DISTRIBUTION; NONUNIFORM; NONUNIFORMITY; SPIN TRANSFER; SPIN-VALVES; VORTEX CHIRALITY; VORTEX MOTION; ZERO FIELDS;

MAGNETIZATION; STEREOCHEMISTRY;

OPTICAL INSTRUMENTS;

EID: 77956234145     PISSN: 00036951     EISSN: None     Source Type: Journal    
DOI: 10.1063/1.3441405     Document Type: Article

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18. We note however that variation in time of even uniform planar polarization p can have a similar effect on the vortex core as the variation in p in space discussed in this work. Thus, a moving uniform planar polarizer can in principle excite the vortex motion.
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23. We obtain the core radius b by fitting the simulated static vortex profile with the Ansatz (2), which gives b=16 nm and the parameter =1.46 is found using the numerical procedure described in Ref. The first critical current can be captured by the analytical model by taking into account the higher order terms in W (a) and W (a) for a≈b, an issue that is going beyond the scope of the present work.