Manuel Valvidares

Fieldlike and antidamping spin-orbit torques in as-grown and annealed Ta/CoFeB/MgO layers

We present a comprehensive study of the current-induced spin-orbit torques in perpendicularly magnetized Ta/CoFeB/MgO layers. The samples were annealed in steps up to 300 \ifmmode^\circ\else\textdegree\fi{}C and characterized using x-ray-absorption spectroscopy, transmission electron microscopy, resistivity, and Hall effect measurements. By performing adiabatic harmonic Hall voltage measurements, we show that the transverse (fieldlike) and longitudinal (antidampinglike) spin-orbit torques are composed of constant and magnetization-dependent contributions, both of which vary strongly with annealing. Such variations correlate with changes of the saturation magnetization and magnetic anisotropy and are assigned to chemical and structural modifications of the layers. The relative variation of the constant and anisotropic torque terms as a function of annealing temperature is opposite for the fieldlike and antidamping torques. Measurements of the switching probability using sub-\ensuremath{\mu}s current pulses show that the critical current increases with the magnetic anisotropy of the layers, whereas the switching efficiency, measured as the ratio of magnetic anisotropy energy and pulse energy, decreases. The optimal annealing temperature to achieve maximum magnetic anisotropy, saturation magnetization, and switching efficiency is determined to be between 240 and 270 \ifmmode^\circ\else\textdegree\fi{}C.

Absence of magnetic proximity effects in magnetoresistive Pt/CoFe2O4 hybrid interfaces

Ultrathin Pt films grown on insulating ferrimagnetic

Electronic and spin states of SrRuO3 thin films: An x-ray magnetic circular dichroism study

\mathrm{CoF}{\mathrm{e}}_{2}{\mathrm{O}}_{4}

Magnetic stability against calcining of microwave-synthesized CoFe2O4 nanoparticles

(111) epitaxial films display a magnetoresistance upon rotating the magnetization of the magnetic layer. We report here x-ray magnetic circular dichroism (XMCD) recorded at Pt-

Superparamagnetism-induced mesoscopic electron focusing in topological insulators

{L}_{2,3}

Unraveling dzyaloshinskii-moriya interaction and chiral nature of graphene/cobalt interface

and Pt-

Direct observation of multivalent states and 4f → 3d charge transfer in Ce-doped yttrium iron garnet thin films

{M}_{3}

Probing the evolution of antiferromagnetism in multiferroics

edges. The results indicate that the Pt magnetic moment, if any, is below the detection limit (

Molecular orientation in soft matter thin films studied by resonant soft x-ray reflectivity

l0.001\phantom{\rule{0.16em}{0ex}}{\ensuremath{\mu}}_{\mathrm{B}}/\mathrm{Pt}

Interface-Assisted Sign Inversion of Magnetoresistance in Spin Valves Based on Novel Lanthanide Quinoline Molecules

), thus strongly favoring the view that the presence of