On Friday, the 12th Of May 2017 at 10h00, Van Tuong PHAM from UGA (DRF/INAC/SPINTEC), will defence his thesis “Ferromagnetic/nonmagnetic nanostructures for the electrical measurement of the spin Hall effect and the detection of domain walls”

Place : Amphithéâtre du CNRS bâtiment A-3ème étage – 25 rue des Martyrs, Grenoble

Spin−orbitronics is based on the ability of spin−orbit interactions to achieve the conv ersion between charge currents and pure spin currents. As the precise evaluation of the conversion efficiency becomes a crucial issue, the need for straightforward ways to observe this conversion has emerged as one of the main challenge in spintronics. This thesis focuses on the study of a new electrical device to characterize the spin Hall effect, and on the detection of magnetic domain walls in nanowires using the direct or the inverse spin Hall effect. The first chapter describes basic spintronic concepts and the state-of-the-art concerning the spin Hall effect detection. In the second chapter, a new ferromagnetic/nonmagnetic nanostructure is proposed, in which it is possible to realize the spin-charge interconversion. This nanostructure is used to quantify the spin Hall angle and the spin diffusion length of Pt. The same technique is then used in the third chapter to characterize the spin Hall effect in different metals and Au-based alloys. The fourth chapter focuses on the role of the ferromagnetic/nonmagnetic interface, which is in particular found to be very important in the NiFe/Pt system. In the last chapter of this thesis, a new method is presented to detect electrically magnetic domain walls by direct or the inverse spin Hall effect.

Jury :
Dafiné RAVELOSONA, Université Paris Sud
David HALLEY, IPCMS
Stefania PIZZINI, Institut Néel
Olivier FRUCHART, CNRS-SPINTEC
Laurent VILA, CEA-SPINTEC
Jean-Philippe ATTANE, UGA-SPINTEC