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Role of SSW on thermal-gradient induced domain-wall dynamics
M A S Akanda1, M T Islam1,2, X R Wang3,4
1Physics Discipline, Khulna University, Khulna 9208, Bangladesh.
Summary
Thermal gradients drive domain wall motion in nanowires via magnonic momentum transfer. Unexpectedly, domain wall velocity increases with damping due to traveling spin waves, not standing ones.
Area of Science:
- Spintronics
- Condensed Matter Physics
- Materials Science
Background:
- Domain wall (DW) dynamics are crucial for spintronic devices like racetrack memory.
- Thermal gradients (TG) offer a potential method for controlling DW motion.
Purpose of the Study:
- Investigate thermal gradient (TG) induced domain wall (DW) dynamics in a uniaxial nanowire.
- Understand the influence of Gilbert damping and nanowire length on DW velocity.
Main Methods:
- Simulations based on the Stochastic-Landau-Lifshitz-Gilbert equation.
- Analysis of domain wall velocities under varying thermal gradients, damping coefficients, and nanowire lengths.
Main Results:
- TG linearly increases DW velocity through magnonic angular momentum transfer.
- DW velocity unexpectedly increases with damping up to a critical value, attributed to the interplay of standing and traveling spin waves.
- DW velocity saturates with increasing nanowire length.
Conclusions:
- Findings provide fundamental insights into TG-driven DW dynamics.
- Demonstrates the potential for utilizing Joule heat in spintronic devices.
- Highlights the counterintuitive role of damping in controlling DW motion.
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