Unidirectional thermal effects in current-induced domain wall motion.

Area of Science:

• Spintronics
• Condensed Matter Physics
• Materials Science

Background:

• Magnetic domain walls (DWs) are crucial for magnetic storage technologies.
• Understanding factors influencing DW motion is key for device optimization.
• Current-induced DW motion is a well-established phenomenon.

Purpose of the Study:

• To experimentally investigate thermal effects on magnetic domain wall displacement in nickel-iron (NiFe) nanostrips.
• To differentiate thermal contributions from current-induced motion.
• To identify the underlying physical mechanism responsible for thermally driven DW motion.

Main Methods:

• Utilizing nanosecond current pulses to induce domain wall motion in NiFe nanostrips.
• Precisely controlling and measuring heat dissipation within the nanostrips.
• Employing heat diffusion modeling to analyze temperature profiles.
• Quantitatively analyzing experimental data to determine forces acting on domain walls.

Main Results:

• Observed unidirectional motion of magnetic domain walls towards hotter regions of the nanostrips.
• Demonstrated that this motion is dependent on the temperature profile along the nanostrip.
• Showed that thermal effects contribute to DW displacement beyond classical thermodynamic pressure.

Conclusions:

• Thermal gradients significantly influence magnetic domain wall dynamics in NiFe nanostrips.
• The observed unidirectional motion is attributed to a temperature profile, likely driven by the magnonic spin Seebeck effect.
• This finding introduces a new mechanism for controlling magnetic domain walls, relevant for future spintronic devices.