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Updated: Jul 7, 2026
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Fabrication of Schottky Diodes on Zn-polar BeMgZnO/ZnO Heterostructure Grown by Plasma-assisted Molecular Beam Epitaxy
Published on: October 23, 2018
Spin diode based on Fe/MgO double tunnel junction.
A Iovan1, S Andersson, Yu G Naidyuk
1Nanostructure Physics, Royal Institute of Technology, 10691 Stockholm, Sweden.
Nano Letters
|February 21, 2008
Summary
Researchers developed a novel spin diode using a nanoscale Fe/MgO double tunnel junction. This semiconductor-free device acts as an efficient on/off spin switch with record magnetoresistance, promising for advanced electronics.
Area of Science:
- Spintronics
- Condensed Matter Physics
- Materials Science
Background:
- Spin diodes are crucial for next-generation electronic devices.
- Existing spin diodes often rely on semiconductors or lack efficiency.
- Developing semiconductor-free, high-performance spin diodes is an active research area.
Purpose of the Study:
- To demonstrate a novel semiconductor-free spin diode.
- To investigate the spin-valve and diode effects in a nanoscale Fe/MgO double tunnel junction.
- To explore the potential of this device for memory and logic applications.
Main Methods:
- Fabrication of a nanoscale Fe/MgO-based double tunnel junction.
- Experimental characterization of the device's electrical transport properties.
- Analysis of spin-dependent tunneling and resonant tunneling phenomena.
Main Results:
- The device exhibited a near-perfect spin-valve effect.
- A strong diode effect (approximately 100) was observed.
- Record-high magnetoresistance exceeding 1000% was achieved, functioning as an on/off spin switch.
Conclusions:
- A new device principle based on resonant tunneling in a ferromagnetic double tunnel junction was demonstrated.
- The high magnetoresistance and diode effect indicate significant potential for memory and reprogrammable logic.
- This semiconductor-free approach offers a promising pathway for advanced spintronic devices.
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