Micromagnetic simulations of magnetization dynamics in a nanowire induced by a spin-polarized current injected via a point contact

التفاصيل البيبلوغرافية
العنوان: Micromagnetic simulations of magnetization dynamics in a nanowire induced by a spin-polarized current injected via a point contact
المؤلفون: Ilya Krivorotov, Carl Boone, D. V. Berkov
المصدر: Physical Review B. 83
بيانات النشر: American Physical Society (APS), 2011.
سنة النشر: 2011
مصطلحات موضوعية: Physics, Condensed Matter::Materials Science, Magnetization dynamics, Magnetization, Condensed matter physics, Field (physics), Oscillation, Nanowire, Condensed Matter Physics, Nanomagnet, Excitation, Electronic, Optical and Magnetic Materials, Magnetic field
الوصف: We present a detailed numerical analysis of the magnetization auto-oscillations induced in a thin NiFe nanowire by a direct spin-polarized current injected via a square-shaped CoFe nanomagnet [a system experimentally studied in Boone et al. Phys. Rev. B 79, 140404 (2009).]. We demonstrate that all auto-oscillation modes in the nanowire are localized under the nanocontact for magnetic field applied in the plane of the nanowire. This mode localization is induced by a strong, stray magnetic field acting on the NiFe nanowire from the CoFe current injector. We find that the auto-oscillation frequency, power, and the frequency shift with the current strongly depend on the exchange constant of NiFe. We also find that the auto-oscillation power depends nonmonotonically on the CoFe saturation magnetization, and we demonstrate that this effect has its origin in resonant excitation of the CoFe eigenmodes by magnetization oscillations in the NiFe nanowire. The calculated dependence of the oscillation frequency on current is in good agreement with the experiment. However, the agreement between theory and experiment for the oscillation power is unsatisfactory. Finally, we have shown that an auto-oscillatory mode propagating along the nanowire in the system under study is possible when a sufficiently strong out-of-plane field is applied.
تدمد: 1550-235X
1098-0121
URL الوصول: https://explore.openaire.eu/search/publication?articleId=doi_________::e734010e42077146e033ed271f4acc95
https://doi.org/10.1103/physrevb.83.054420
حقوق: OPEN
رقم الأكسشن: edsair.doi...........e734010e42077146e033ed271f4acc95
قاعدة البيانات: OpenAIRE