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Theoretical Calculation and Experimental Verification for Dislocation Reduction in Germanium Epitaxial Layers with Semicylindrical Voids on Silicon
Published on: July 17, 2020
Lateral spin injection in germanium nanowires.
En-Shao Liu1, Junghyo Nah, Kamran M Varahramyan
1Microelectronics Research Center, The University of Texas, Austin, Texas 78758, USA.
Nano Letters
|August 17, 2010
Summary
We achieved efficient spin injection and transport in germanium nanowires using ferromagnetic contacts. This demonstrates germanium
Area of Science:
- Semiconductor spintronics
- Materials science
- Condensed matter physics
Background:
- Spin-based electronics offer potential advantages over conventional charge-based electronics.
- Germanium is a promising material for spintronics due to its compatibility with existing silicon technology.
- Efficient spin injection and long spin diffusion lengths are crucial for practical spintronic devices.
Purpose of the Study:
- To demonstrate lateral spin injection and detection in germanium nanowires.
- To investigate the role of contact resistance engineering in achieving efficient spin injection.
- To determine the spin diffusion length in germanium nanowires.
Main Methods:
- Fabrication of germanium nanowires with ferromagnetic metal contacts.
- Utilizing tunnel barriers for contact resistance engineering.
- Electrical measurement of spin-polarized electron transport.
- Analysis based on spin diffusion theory.
Main Results:
- Lateral spin injection and detection were successfully demonstrated in germanium nanowires.
- A specific contact resistance window was identified for optimal spin injection, highlighting the importance of conductivity matching.
- Spin diffusion length in germanium nanowires was found to be greater than 100 micrometers at 4.2 K.
Conclusions:
- Germanium nanowires are a viable platform for spintronic devices.
- Contact resistance engineering is critical for efficient spin injection in germanium nanowires.
- The long spin diffusion length in germanium at low temperatures is highly promising for future spintronic applications.
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