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Published on: August 2, 2019
AC conductivity of a quantum Hall line junction
1Center for High Energy Physics, Indian Institute of Science, Bangalore 560 012, India.
Summary
We developed a microscopic model for AC conductivity in quantum Hall edge junctions. Interactions and tunneling influence conductivity oscillations, revealing potential metallic or insulating phases.
Area of Science:
- Condensed Matter Physics
- Quantum Hall Effect
- Mesoscopic Systems
Background:
- Quantum Hall edges are crucial in condensed matter systems.
- Understanding AC conductivity in these junctions is key to their electronic properties.
Purpose of the Study:
- To develop a microscopic model for AC conductivity in finite quantum Hall edge line junctions.
- To investigate the influence of interactions and tunneling on conductivity.
Main Methods:
- Microscopic modeling of AC conductivity.
- Analysis of density-density interactions and local tunneling conductance.
- Renormalization group analysis.
Main Results:
- Derived expressions for AC conductivity as a function of frequency, junction length, and tunneling.
- Reproduced DC limit results and generalized them for interacting systems.
- Observed significant AC conductivity oscillations at low tunneling, diminishing with increased tunneling.
Conclusions:
- The AC conductivity exhibits frequency-dependent oscillations influenced by tunneling strength.
- Renormalization group analysis indicates the possibility of metallic or insulating phases.
- Results have implications for low-temperature experimental studies of quantum Hall edge junctions.
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