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Updated: Sep 4, 2025
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Probe Type II Band Alignment in One-Dimensional Van Der Waals Heterostructures Using First-Principles Calculations
Published on: October 12, 2019
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Even-odd chain dependent spin valve effect on a zigzag biphenylene nanoribbon junction
Lin Zhang1, Peiqing Tong2,3
1Department of Applied Physics, College of Science, Nanjing Forestry University, Nanjing 210037, People's Republic of China.
Summary
Zigzag biphenylene nanoribbons exhibit an even-odd chain spin valve effect, controlling electron spin flow. This phenomenon, tunable by magnetic fields and energy, offers potential for novel spintronic devices.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Mechanics
Background:
- The spin valve effect, crucial for spintronics, has been theoretically predicted in honeycomb graphene-like materials.
- Previous research suggested an even-odd chain dependence in these effects.
Purpose of the Study:
- To confirm the existence of the even-odd chain dependent spin valve effect in zigzag biphenylene nanoribbon (ZBN) junctions.
- To investigate the tunability of this effect using system parameters and explore ZBNs as spin generators and filters.
Main Methods:
- Modeling ZBN junctions with varying even and odd chains.
- Applying local Rashba spin-orbit coupling (SOC) and a homogeneous magnetic field.
- Calculating spin-dependent conductance spectra.
Main Results:
- The even-odd chain phenomenon was confirmed in ZBN junctions.
- Spin-up (down) electrons were inhibited (allowed) in even (odd)-chain ZBNs due to pseudo-parity conservation and tunable band gaps.
- Spin valve states were modulated by Fermi energy, magnetic flux, and Rashba SOC.
- ZBNs demonstrated gate-tunable spin generation (100% polarization) and filtering (27% spin-converting electrons).
Conclusions:
- Zigzag biphenylene nanoribbons exhibit controllable spin valve properties based on even-odd chain structures.
- The findings suggest potential applications in designing multi-parameter controllable spin valves using novel carbon allotropes.
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