Modélisation micromagnétique de dynamique d'aimantation pilotée par transfert de spin dans des nanopiliers

Abstract : The goal of this PhD thesis has been two-fold: test a Finite Element micromagnetic solver (feeLLGood), and study spin-transfer-driven magnetisation dynamics to understand experimental measurements of several spintronic devices. Two time schemes implemented in the code have been benchmarked against other solvers, in particular against a Finite Difference code (ST_GL-FFT). Comparisons of the simulation results confirmed the accuracy of feeLLGood and showed artefacts in Finite Difference simulations. On the other hand, numerical simulations have allowed in-depth analyses of three types of spintronic device. (1) Frequency jumps have been studied in a planar Spin Torque Oscillator. Thanks to spectral mapping techniques, the jumps were shown to be linked to the excitation of non-linear modes. (2) The state diagram of a perpendicular-polariser/planar-free-layer Spin Torque Oscillator has been explored, showing various oscillation modes depending on the initial state. Moreover, discrepancy between Finite Difference and Finite Element simulations showed the effect of a staircase-like edge. (3) Precessional switching induced by spin transfer torque has been simulated to understand the influence of the polariser's stray field on the switching probability. A good agreement with experimental measurements of STT-MRAM has been found.
Complete list of metadatas

Cited literature [118 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-01078784
Contributor : Abes Star <>
Submitted on : Thursday, October 30, 2014 - 11:36:44 AM
Last modification on : Thursday, April 4, 2019 - 9:44:02 AM
Long-term archiving on : Monday, February 2, 2015 - 3:55:53 PM

File

32632_VAYSSET_2013_archivage.p...
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-01078784, version 1

Collections

Citation

Adrien Vaysset. Modélisation micromagnétique de dynamique d'aimantation pilotée par transfert de spin dans des nanopiliers. Autre [cond-mat.other]. Université de Grenoble, 2013. Français. ⟨NNT : 2013GRENY062⟩. ⟨tel-01078784⟩

Share

Metrics

Record views

572

Files downloads

358