Ionic-liquid gating of perpendicularly magnetised CoFeB/MgO thin films.

Authors :: Liu, Y. T.
Agnus, G.
Ono, S.
Ranno, L.
Bernand-Mantel, A.
Soucaille, R.
Adam, J.-P.
Langer, J.
Ocker, B.
Ravelosona, D.
Herrera Diez, L.
Source :: Journal of Applied Physics; 2016, Vol. 120 Issue 2, p023901-1-023901-5, 5p, 1 Color Photograph, 1 Diagram, 3 Graphs
Publication Year :: 2016
Abstract: We present the modulation of anisotropy field, coercivity, and domain wall (DW) velocity in CoFeB/MgO thin films with perpendicular anisotropy by applying voltages across an ionic liquid gate. Domain wall velocities in the creep regime can be modulated by a factor of 4.2, and the anisotropy field of the device can be modulated by 40 mT when going from +0.8V to -0.8V. The applied E-fields are seen to significantly influence DWs' pinning, depinning, and nucleation processes. In addition, we report on the evolution of the magnetic properties of the liquid/solid device as a function of time going from the pristine CoFeB/MgO film through device fabrication and operation up to one month. These results show that the solid/liquid device structure based on CoFeB/MgO thin films can be an efficient way to control magnetic properties with voltages below 1V. [ABSTRACT FROM AUTHOR]