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Interface-driven spin filtering and diode effects in van der Waals junctions based on magnetic metal-organic
Mingqiang Ge1, Ziqiang Liu1, Tong Chen1
1School of Energy and Mechanical Engineering, Energy Materials Computing Center, Jiangxi University of Science and Technology, Nanchang 330013, China. lin_huang@hnu.edu.cn.
Physical Chemistry Chemical Physics : PCCP
|March 10, 2025
Summary
Interface engineering significantly enhances spin-polarized transport in molecular junctions. Modulating the tunneling barrier and dipole in Cr(pyz)2 van der Waals junctions enables semiconductor-to-half-metal transitions and boosts spin filtering efficiency.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Molecular junctions offer tunable electronic properties.
- Interface engineering is crucial for optimizing spin-polarized transport.
- Van der Waals heterostructures provide a platform for novel electronic devices.
Purpose of the Study:
- To investigate the impact of interface modulation on spin transport in Cr(pyz)2-based van der Waals junctions.
- To explore the mechanism of spin filtering efficiency (SFE) enhancement.
- To assess the potential for diode-like behavior through molecular modification.
Main Methods:
- First-principles calculations.
- Nonequilibrium Green's function (NEGF) method.
- Analysis of charge transfer and dipole formation at the molecule-electrode interface.
Main Results:
- Tuning the tunneling barrier and interface dipole regulates spin transport properties.
- Charge redistribution in Cr(pyz)2 induces a semiconductor-to-half-metal transition.
- Partial fluorination enhances electronegativity, induces dipole moments, and leads to diode-like behavior, improving spin filtering efficiency (SFE).
Conclusions:
- Interface engineering is a powerful strategy for controlling spin transport in molecular junctions.
- Cr(pyz)2-based van der Waals junctions exhibit significant interface-driven spin filtering and diode effects.
- These findings provide a pathway for designing advanced spintronics devices.
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