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Published on: July 2, 2018
Current density waves in open mesoscopic rings driven by time-periodic magnetic fluxes
1Quantum Optoelectronics Laboratory, Southwest Jiaotong University, Chengdu 610031, People's Republic of China.
Summary
Researchers explored quantum transport in mesoscopic rings with time-periodic magnetic flux. They found that oscillating fields can generate net electrical currents via photon-assisted processes, a novel finding for single-reservoir systems.
Area of Science:
- Condensed Matter Physics
- Quantum Transport Phenomena
- Mesoscopic Physics
Background:
- Extensive studies exist on quantum coherent transport in open mesoscopic Aharonov-Bohm rings driven by static magnetic fluxes.
- Understanding electron transport in systems influenced by time-dependent fields is crucial for quantum device applications.
Purpose of the Study:
- To investigate quantum transport of electrons in an open mesoscopic ring subjected to a time-periodic magnetic flux.
- To explore the generation of net electrical currents in such systems, particularly in single-reservoir leads.
Main Methods:
- Utilized quantum waveguide theory.
- Applied the Floquet theorem to analyze systems with time-periodic driving.
- Investigated the role of photon-assisted processes in electron transport.
Main Results:
- Predicted the excitation of current density waves along the open mesoscopic ring.
- Demonstrated the possibility of generating a net current in a single-reservoir lead connected to the ring.
- Showcased that these effects are driven by photon-assisted processes due to electron-oscillating field interactions.
Conclusions:
- Time-periodic magnetic fluxes can induce net electrical currents in mesoscopic rings, even in single-reservoir configurations.
- Photon-assisted processes are key to understanding this current generation mechanism.
- The generated currents are tunable by the amplitude and frequency of the oscillating magnetic flux.
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