Group of Nanomagnetism and Magnetization Processes

Converse magnetoelectric coupling in hybrid Ni₉₀Fe₁₀/LiNbO₃(0 1 4) heterostructures

D. Rizo-Molina, A.Begué, M. Jaafar, R. Ranchal

Materials Today Communications 53, 115320 (2026).

DOI: 10.1016/j.mtcomm.2026.115320

This work focuses on the fabrication of hybrid magnetoelectric heterostructures formed by magnetostrictive Ni₉₀Fe₁₀ films electrodeposited on Y-cut 128° LiNbO₃ (LN) piezoelectric substrates, a cut widely used for surface acoustic waves (SAWs). X-ray diffractometry (XRD) measurements with out-of-plane (OOP) applied voltage demonstrate the deformation of the magnetostrictive film despite the partial presence of nonpiezoelectric LiNbO₂ (LNO) in the substrates. Magneto-optical Kerr effect (MOKE) measurements reveal how the LN substrate induces an uniaxial in-plane (IP) magnetic anisotropy in the Ni₉₀Fe₁₀ film with the easy axis along LN ̅ and the hard axis along LN directions, respectively. Analysis of the strain tensor of the LN substrate confirms that the experimentally observed changes in the Ni₉₀Fe₁₀ magnetostrictive layer are consistent with the mechanical deformation induced by the substrate. Voltage-dependent MOKE hysteresis loops show converse magnetoelectric couplings of   = (-0.10 ± 0.02) μs/m in the hard magnetic axis of the Ni₉₀Fe₁₀ layer, and  = (-0.16 ± 0.01) μs/m at 45° with respect to it, despite the presence of the non-piezoelectric LNO secondary phase in the commercial substrate. The robustness of the magnetoelectric coupling is confirmed, exhibiting no visible degradation in the remanence signal after dozens of polarization cycles. These results evidence voltage control of magnetic anisotropy in the Ni₉₀Fe₁₀/LN heterostructure, providing a low-cost, lead‑free system to control the magnetic axes.

This work has been financially supported through the projects PID2021–122980OB-C51 (AEI/FEDER), PID2024–155385NB-C33, PID2024–157112OB-C51 (AEI/FEDER) and PDC2025–165978-I00 of the Spanish Ministry of Science and Innovation. We thank both the CAI X-ray Diffraction Unit and Ion Implantation Unit at Complutense University of Madrid (Spain) for their valuable technical assistance

«Domain Wall Rebounds Driven by Competing Entropic and Spin Transfer Torques in Cylindrical Nanowires»

Elias Saugar, Jorge Marqués-Marchán, Sara Catalano, Agustina Asenjo, Michael Foerster, Miguel Angel Niño, Manuel Vazquez, Fèlix Casanova, Arantxa Fraile Rodríguez, Rafael P. Del Real, Oksana Chubykalo-Fesenko, Cristina Bran

Advanced Functional Materials,2026

DOI: 10.1002/adfm.202525734

Controlling domain walls in cylindrical geometries through energy-efficient spintronic methods is a key challenge for advancing future three dimmensional(3D) nanotechnologies.Here we used theX-ray Magnetic Circular Dichroism combined with Photoemission Electron Microscopy (XMCD-PEEM) technique to investigate domain wall dynamics in cylindrical magnetic nanowires under nanosecond current pulses. We found that small current densities (∼4×1011A/m2) effectively move domain walls and saturate the nanowire. Surprisingly, when the current density is further increased, the domain walls are not expelled from the nanowire. Instead, they rebound from the nanowire ends, with the rebound distance increasing as the pulse duration increases. Our modeling reveals that spin transfer torque dominates at lower currents, whereas at higher currents, it competes with a thermal gradient which pushes domain walls toward the nanowire center. These results underline the importance of thermal effects in cylindrical geometries and their implications for the design of robust spintronic devices.

DWs movement under high amplitude current pulses. XMCD-PEEM series of images taken after a pulse of 8×1011 A/m2 was applied repeatedly for (A) 10ns and (B) 20ns, respectively. Scale bar 1μm.

 

The authors acknowlodge the financial support from Spanish Ministry of Innovation and Science under projects PID2022-137567NB-C21 and RED2022-134649-T and the project Mag4TIC-CM(TEC-2024TEC-380)from the government of Madrid.

Last week, Jorge A.  presented his work entitled Monolayers of Janus Nanoparticles for glial regeneration through magnetostrictive effect mediated by Terfenol-D as an oral presentation at the 5th International Conference on Nanomaterials Applied to Life Sciences 2026. This study investigates the effects generated by magnetostrictive platforms for the stimulation of cell proliferation.

 

Daniel Rizo is our new PhD student.  During his PhD, he will study Non magnetic stimuli to modulate magnetic phenomena, under the supervision of Miriam Jaafar and Rocío Ranchal (UCM).