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Published on: January 19, 2018
Electric-field-dependent spin polarization in GdN spin filter tunnel junctions
Avradeep Pal1, K Senapati, Z H Barber
1Department of Materials Science and Metallurgy, University of Cambridge, Pembroke Street, Cambridge, CB2 3QZ, UK.
Advanced Materials (Deerfield Beach, Fla.)
|July 30, 2013
Summary
Gadolinium nitride (GdN) tunnel junctions achieve over 90% spin polarization and high conductance. An unusual low-bias peak is linked to bias-dependent spin polarization and magneto-electric coupling in the Schottky barrier.
Area of Science:
- Solid State Physics
- Materials Science
- Spintronics
Background:
- Ferromagnetic semiconductor tunnel junctions are key for spintronic devices.
- Gadolinium nitride (GdN) offers unique magnetic and electronic properties.
- Controlling spin polarization in tunnel junctions is crucial for device performance.
Purpose of the Study:
- To investigate spin polarization and conductance in GdN-based tunnel junctions.
- To understand the origin of the low-bias conductance peak.
- To explore the role of magneto-electric coupling in device characteristics.
Main Methods:
- Fabrication of tunnel junctions with GdN ferromagnetic semiconductor barriers and NbN electrodes.
- Electrical transport measurements, including low-bias conductance spectroscopy.
- Analysis of spin polarization and its bias dependence.
Main Results:
- Achieved spin polarization exceeding 90% with high conductance.
- Observed an unusual low-bias conductance peak.
- Demonstrated a strong bias-dependence of spin polarization.
- Identified strong magneto-electric coupling within the double Schottky barrier.
Conclusions:
- GdN-based tunnel junctions are promising for high-performance spintronics.
- The low-bias peak is attributed to bias-dependent spin polarization and magneto-electric coupling.
- These findings highlight the potential of GdN for advanced spin-based electronic devices.
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