Research team Theory/Simulation, within the Concepts group
Time-resolved magnetic imaging of Œrsted-field effects in cylindrical nanowires (August 31st, 2021)
We have conducted time-resolved stroboscopic imaging of the magnetization dynamics in cylindrical nanowires subject to nanosecond pulses of electric current. These confirm the dramatic impact of the Œrsted field in the cylindrical geometry. Through a thorough quantitative analysis, we extract features during the pulse of current, such as the azimuthal component of magnetization in magnetic […]
Read moreRoute towards efficient magnetization reversal driven by voltage control of magnetic anisotropy (July 06th, 2021)
Using a macrospin approach, we carried out a systematic analysis of the role of the voltage controlled magnetic anisotropy on the magnetization dynamics of nanostructures with out-of-plane magnetic anisotropy. Diagrams of the magnetization switching have been computed depending on the material and experiment parameters thus allowing predictive sets of parameters for optimum switching experiments. Voltage […]
Read moreWe report very large spin transfer torque driven domain wall velocities, approaching 3000 m/s, in rare-earth free ferrimagnetic Mn4-xNixN thin films close to the angular momentum compensation point. We also observe a reversal of the domain wall motion direction after the angular momentum compensation point. The interest towards ferrimagnets has recently grown because of their […]
Read moreHelium ions put skyrmions on the track (May 20th, 2021)
Magnetic skyrmions are local twists of the magnetization which hold promise as nm scale information carrier. Here we demonstrate that focused He+-ion irradiation can be used to create and guide skyrmions in magnetic tracks. This work opens up a new path to manipulate magnetic skyrmions in magnetic memory and logic devices. Magnetic skyrmions are currently […]
Read moreAtomistic spin simulations have been carried out to study the probability of all-optical switching of [Tb/Co] multilayered thin films. Playing with the composition of the sample, the material parameters and the fluence of the laser pulse we have shown the possibility to get single-shot all-optical switching. Since the first experimental observation of all-optical switching phenomena, […]
Read moreGiant Perpendicular Magnetic Anisotropy Enhancement in MgO-Based Magnetic Tunnel Junction by Using Co/Fe Composite Layer (April 26th, 2021)
Magnetic tunnel junctions with perpendicular anisotropy form the basis of the spin-transfer torque magnetic random-access memory (STT-MRAM), which is nonvolatile, fast, dense, and has quasi-infinite write endurance and low power consumption. Here, an alternative design of tunnel junctions comprising FeCoFe|MgO storage layers with greatly enhanced perpendicular magnetic anisotropy (PMA) is proposed, leveraging the interfacial PMA […]
Read moreTheoretical study of current induced domain wall motion in magnetic nanotubes with azimuthal magnetization (April 12th, 2021)
We report a theoretical overview of the magnetic domain wall behavior under an electric current in infinitely long nanotubes with azimuthal magnetization. We highlight effects that, besides spin-transfer torques already largely understood in flat strips, arise specifically in the tubular geometry: the Œrsted field and curvature-induced magnetic anisotropy resulting both from the exchange interaction and […]
Read moreDefence Thesis – Modeling of domain walls dynamics in circular cross-section nanowires (March 09th, 2021)
On Monday, the 15th Of March 2021 at 13h30, Arnaud De Riz will defence his thesis “Modeling of domain walls dynamics in circular cross-section nanowires” supervised by D. Gusakova and J.-Ch. Toussaint Place: ONLINE Link to participate on-line: https://grenoble-inp.zoom.us/j/93099958160 Code: 075714 Abstract: This thesis studies theoretically the magnetic domain wall behavior in cylindrical wires subjected […]
Read moreSeminar – Spin dynamics and transport at the nanoscale (March 08th, 2021)
On March 17 at 15:00, Manuel dos Santos Dias from Peter Grünberg Institut and Institute for Advance Simulation, Forschungszentrum Jülich, Germany will give us a seminar entitled : Spin dynamics and transport at the nanoscale Place : The seminar will be given via skype (ask link to alain.marty@cea.fr ) abstract : In this talk, I […]
Read moreMeasurement of the Spin Absorption Anisotropy in Lateral Spin Valves (March 04th, 2021)
The spin absorption process in a ferromagnetic material depends on the spin orientation relatively to the magnetization. Using a ferromagnet to absorb the pure spin current created within a lateral spin valve, we evidence and quantify a sizable orientation dependence of the spin absorption in Co, CoFe, and NiFe. These experiments allow us to determine […]
Read more