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Quasiballistic quantum transport through Ge/Si core/shell nanowires
D Kotekar-Patil1, B-M Nguyen2, J Yoo2
1Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA 15260, United States of America.
Nanotechnology
|July 14, 2017
Summary
We observed quantum transport signatures in germanium/silicon nanowires, revealing interference patterns and conductance plateaus. These findings are crucial for developing advanced spin and topological quantum devices.
Area of Science:
- Quantum physics
- Condensed matter physics
- Nanotechnology
Background:
- Quantum transport phenomena are essential for next-generation electronic devices.
- Germanium/silicon core/shell nanowires offer unique properties for exploring quantum effects.
Purpose of the Study:
- To investigate ballistic quantum transport of holes in Ge/Si core/shell nanowires.
- To analyze the impact of silicon shell thickness on quantum transport signatures.
- To explore potential applications in spin and topological quantum devices.
Main Methods:
- Low-temperature measurements of conductance in Ge/Si core/shell nanowires.
- Observation and analysis of Fabry-Pérot interference patterns.
- Investigation of magnetic field evolution of conductance plateaus.
Main Results:
- Observed Fabry-Pérot interference and conductance plateaus (multiples of 2e²/h) at zero magnetic field.
- Determined large effective Landé g-factors from magnetic field studies.
- Confirmed ballistic effects in nanowires with 1-3 nm silicon shells, absent in bare germanium wires.
Conclusions:
- Ge/Si core/shell nanowires exhibit distinct quantum transport signatures.
- Ballistic transport is sensitive to silicon shell thickness.
- These results provide a foundation for developing novel quantum devices.
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