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

ABSTRACT 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 the X‐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 × 10 1 1 A/m 2 ) 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.