The MISSION project aims at lowering the power consumption in spin Hall effect (SHE) promoted spin-orbit torque (SOT) switching processes. This process is an extremely promising alternative to spin transfer torque for the manipulation of magnetization in spintronics devices such as Magnetic Random Access Memories. Current SOT-based systems consist of a nonmagnetic (NM) conducting layer with large spin orbit coupling, generating a pure spin current through SHE, and a ferromagnetic layer (FM), into which the spin current is transmitted by SOT. We plan to introduce, for the first time a ferromagnetic magnetoelectric (ME) material, i.e. a multifunctional material, as the FM layer in SHE promoted SOT based devices. This will make them adaptable via an electric field. We are aiming, through this ME-based modulation, at a SHE induced magnetization reversal necessitating the injection of a less intense charge current in the NM metal layer.
a) The Pc21n orthorhombic structure of Ga2-xFexO3 (GFO), showing the double hexagonal close-packed stacking of oxygens (ABAC), and the 3 octahedral and 1 tetrahedral cationic sites. It is ferrimagnetic at room temparature with a TC of 370 K for x=1.4 and a saturation magnetization of 100 emu/cm3 @ 300 K. It has a linear ME coefficient of ca. 2.10-11 s/m in its bulk form. (b) Schematic diagram of the ME control of spin-orbit torque switching. The current Jc flowing in the Pt layer generates a transverse spin current Js thanks to the spin Hall effect. Js exerts a torque on the magnetization M of the magneto-electric (ME) GFO layer and possibly switch the magnetization M. A top gate voltage is applied in order to exploit the ME properties of the GFO layer.
Mission 6 months meeting – 2019-03-28 – IJL Nancy From left to right, and top to down: Christophe LEFEVRE (IPCMS), François ROULLAND (IPCMS), Karine DUMESNIL (IJL), Sébastien PETIT-WATELOT (IJL), Daniele PREZIOSI (IPCMS), Olivier COPIE (IJL), Suvidyakumar HOMKAR (IPCMS), Elodie MARTIN (IJL), Nathalie VIART (IPCMS, PI) and Carlos ROJAS-SANCHEZ (IJL, local PI) -not present on the picture : Jon GORCHON (IJL) and Benjamin MEUNIER (IPCMS)-
FUNDING : 444k€
SCIENTIFIC PROJECT TIMELINE: 01/10/2018 – 31/03/2022
More on the project on the ANR WebPage of the MISSION project ANR-18-CE24-0008