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Understanding nanoscale temperature gradients in magnetic nanocontacts
S Petit-Watelot1, R M Otxoa, M Manfrini
1Institut d'Electronique Fondamentale, Université Paris-Sud, 91405 Orsay, France.
Physical Review Letters
|February 2, 2013
Summary
We studied temperature profiles in magnetic nanocontacts using spin-torque oscillators. Joule heating effects on resistance were independent of temperature, but vortex nucleation indicated significant local temperature increases.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Spin-torque oscillators are crucial for magnetic device applications.
- Understanding thermal effects in nanocontacts is vital for device performance.
- Joule heating and thermal gradients can influence magnetic dynamics.
Purpose of the Study:
- To determine the temperature profile within magnetic nanocontacts under high current densities.
- To investigate the impact of Joule heating on electrical resistance.
- To correlate temperature increases with magnetization dynamics like vortex nucleation.
Main Methods:
- Experimental measurements of electrical and magnetic properties of nanocontacts.
- Full three-dimensional simulations of heat and current flow.
- Analysis of current-induced vortex nucleation as a thermally activated process.
Main Results:
- The quadratic increase in resistance due to Joule heating was independent of temperature (6–300 K).
- Current-induced vortex nucleation suggests local temperature increases of 147–225 K.
- Simulations confirmed experimental findings and revealed thermal gradients extending up to 450 nm.
Conclusions:
- Local temperature increases significantly impact magnetization dynamics in nanocontacts.
- Joule heating effects are substantial even at low base temperatures.
- Accurate thermal modeling is essential for designing advanced spintronic devices.
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