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Published on: August 2, 2019
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Current noise in three-terminal hybrid quantum point contacts
1Department of Applied Physics, Donghua University, 2999 North Renmin Road, Shanghai 201620, People's Republic of China.
Summary
Current noise in hybrid structures reveals internal dynamics. Increased coupling to normal leads suppresses characteristic noise features, offering insights into Andreev reflection processes.
Area of Science:
- Condensed matter physics
- Quantum transport phenomena
Background:
- Understanding charge transport in hybrid nanostructures is crucial for developing quantum devices.
- Current noise measurements offer a sensitive probe of underlying electronic processes.
Purpose of the Study:
- To investigate the current noise characteristics of three-terminal hybrid structures.
- To explore the utility of noise as a tool for extracting dynamical information.
Main Methods:
- Theoretical analysis of current noise at arbitrary bias voltages in three-terminal hybrid structures.
- Examination of the influence of coupling to a normal lead on noise properties.
Main Results:
- Zero-frequency noise is sensitive to coupling with a normal lead.
- Increased coupling suppresses the multiple-step structure of the Fano factor associated with multiple Andreev reflection.
- Internal dynamics, including Andreev reflection and multiple Andreev reflection, create rich features in the noise spectrum.
Conclusions:
- Current noise is a valuable tool for probing dynamical information in multi-terminal hybrid systems.
- The interplay between coupling and internal dynamics significantly impacts noise signatures.
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