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Published on: August 2, 2019
Temperature-dependent quantum electron transport in 2D point contacts.
1Kotelnikov Institute for Radioengineering and Electronics, Mokhovaya 11-7, Moscow 125009, Russia. krishtop@cplire.ru
Summary
Electron transport through a 2D ballistic point contact shows a temperature-dependent conductance. This effect, driven by Friedel oscillations, is negative for typical experimental conditions.
Area of Science:
- Condensed matter physics
- Mesoscopic physics
- Quantum transport
Background:
- Electron transmission through nanoscale contacts is crucial for quantum devices.
- Low-conductance regimes reveal fundamental quantum phenomena.
- Friedel oscillations significantly influence charge density near impurities.
Purpose of the Study:
- Investigate electron scattering in a 2D ballistic point contact near pinch-off.
- Analyze the temperature dependence of conductance in this regime.
- Determine the impact of electron-electron interactions on conductance.
Main Methods:
- Theoretical analysis of electron transmission.
- Modeling scattering by Friedel oscillations.
- Low-conductance regime calculations.
Main Results:
- Observed a conductance contribution linearly proportional to temperature.
- The sign of this linear term depends on electron-electron interaction range.
- Found a negative sign for this term under relevant experimental parameters.
Conclusions:
- Friedel oscillations introduce a measurable temperature dependence in point contact conductance.
- The sign of this temperature dependence provides insight into interaction ranges.
- Results are relevant for understanding quantum transport in low-dimensional systems.
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