olivier.boulle
On Thursday november 30th, at 9:30, Olivier Boulle (SPINTEC) will defend his HDR entitled :
Spinorbitronics: exploiting spin orbit interaction to manipulate magnetization in ultrathin films
Place : IRIG/SPINTEC, CEA Building 10.05, auditorium 445 (access needs authorization *)
visioconference link : https://webconf.cea.fr/olivier.boulle/WHVLLBWS
If the link does not work, try with skype web App : https://webconf.cea.fr/olivier.boulle/WHVLLBWS?sl=1
or by phone +33 1 69 35 55 10 conf ID : 34380562
Abstract : Spin orbitronics is a new field of research which proposes to exploit spin orbit coupling to manipulate magnetization in magnetic thin films. Spin orbit coupling can be leveraged to prepare spin polarized currents and reverse the magnetization of nanomagnets via the spin orbit torques, or stabilize chiral topological chiral spin textures via the Dzyaloshinskii-Moriya interaction. In this habilitation, I will present my contribution to this field of research over the last ten years.
In a first part, I will discuss my work on SOT-MRAM, a novel magnetic memory where the magnetization state is reversed via spin orbit torques and readout using a magnetic tunnel junction. I will show that magnetization switching can be achieved by current pulses as short as 400 fs in SOT-MRAM and detected with a large electrical signal via the magnetoresistance tunnel effect.
In the second part, I will summarize my work on the current-induced dynamics of magnetic domain walls in ultrathin heavy metal/ferromagnetic films and in particular the impact of the spin orbit torques and Dzyaloshinskii-Moriya interaction.
The third part is dedicated to my activity on magnetic skyrmions, a nanometer scale topologically stable chiral spin textures stabilized by the Dzyaloshinskii-Moriya interaction. I will show that magnetic skyrmions can be stabilized at room temperature in ultrathin Pt/Co/MgO multilayer and manipulated using electrical currents with large velocities. I will then show that skyrmions can be nucleated and stabilized in synthetic antiferromagnets and moved with very large velocities, up to 900 m/s, owing to the cancellation of their topological charge. I will conclude with recent results on the electrical readout of skyrmions in magnetic tunnel junctions.
Jury :
- Giovanni Finocchio, Professeur – Université de Messine (Italie), Rapporteur
- Joo-Von Kim, Directeur de recherche CNRS– C2N, Rapporteur
- Alexandra Mougin, Directrice de recherche CNRS, LPS, Rapportrice
- Vincent CROS, Directeur de Recherche CNRS – UMP CNRS Thales, Examinateur
- Jean-Philippe Attané, Professeur, UGA, Examinateur
(*) Access to CEA requires an entry authorization. request it sufficiently in advance : before November 17th at admin.spintec@cea.fr