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Large local Hall effect in pin-hole dominated multigraphene spin-valves
P K Muduli1, J Barzola-Quiquia, S Dusari
1Division of Superconductivity and Magnetism, Institut für Experimentelle Physik II, Universität Leipzig, Linnéstrasse 5, D-04103 Leipzig, Germany. muduli@physik.uni-leipzig.de
Nanotechnology
|December 11, 2012
Summary
Spurious resistance switching in multigraphene spin-valves was caused by a local Hall effect from tunnel barrier irregularities. This effect may obscure genuine spin injection signals in experiments.
Area of Science:
- Condensed matter physics
- Materials science
- Spintronics
Background:
- Mesoscopic multigraphene spin-valves are promising for spintronics.
- Understanding spin injection efficiency is crucial for device performance.
Purpose of the Study:
- Investigate spurious resistance switching in multigraphene spin-valves.
- Determine the origin of observed switching behavior.
- Assess the impact on spin injection measurements.
Main Methods:
- Performed local and non-local spin-valve measurements.
- Analyzed resistance changes during magnetic field sweeping.
- Investigated the role of tunnel barrier properties.
Main Results:
- Observed spurious switching behavior in local measurements.
- Attributed switching to a local Hall effect from tunnel barrier thickness irregularities.
- Found the local Hall effect to be negligible above 75 K.
- Hypothesized that a strong local Hall effect can hinder spin injection.
Conclusions:
- Local Hall effect due to tunnel barrier roughness can mimic spin injection signals.
- This effect can impede reliable non-local spin transport measurements.
- Careful consideration of tunnel barrier uniformity is essential for accurate spintronic studies in multigraphene.
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