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Silicon Metal-oxide-semiconductor Quantum Dots for Single-electron Pumping
Published on: June 3, 2015
Efficient spin filter using multi-terminal quantum dot with spin-orbit interaction.
1Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan. tyokoyam@rk.phys.keio.ac.jp.
Nanoscale Research Letters
|June 30, 2011
Summary
We developed a novel multi-terminal spin filter utilizing a quantum dot with spin-orbit interaction. This device enhances the spin Hall effect (SHE) through resonant tunneling, achieving over 50% efficiency for spintronic applications.
Area of Science:
- Condensed matter physics
- Spintronics
- Quantum computing
Background:
- Spin-orbit interaction is crucial for spintronic devices.
- Quantum dots offer tunable electronic properties.
- The spin Hall effect (SHE) is a key phenomenon for spin manipulation.
Purpose of the Study:
- To propose and analyze a multi-terminal spin filter based on a quantum dot.
- To investigate the enhancement of the spin Hall effect (SHE) via resonant tunneling.
- To demonstrate the tunability and efficiency of the proposed spin filter.
Main Methods:
- Formulation of the spin Hall effect (SHE) in a three-terminal quantum dot system.
- Analysis of resonant tunneling conditions for SHE enhancement.
- Numerical simulations of a quantum dot spin filter in semiconductor heterostructures.
Main Results:
- Significant enhancement of the spin Hall effect (SHE) when quantum dot level broadening exceeds level spacing.
- Tunable SHE by adjusting the tunnel coupling to the third lead.
- Demonstration of a spin filter with over 50% efficiency under optimized conditions.
Conclusions:
- The proposed multi-terminal quantum dot device effectively functions as a spin filter.
- Resonant tunneling provides a mechanism for significantly enhancing the spin Hall effect (SHE).
- The device's efficiency and tunability make it promising for spintronic applications.
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