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Updated: Sep 18, 2025
05:39
Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
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Quantized two terminal conductance, edge states and current patterns in an open geometry 2-dimensional Chern
Junaid Majeed Bhat1, Abhishek Dhar2, R Shankar1
1International Centre for Theoretical Sciences, Tata Institute of Fundamental Research, Bengaluru 560 089, India.
Summary
This study confirms perfect quantization of two-terminal conductance in 2D topological systems, justifying the Landauer-Buttiker theory. It reveals emergent single-channel behavior and localized currents at insulator corners.
Area of Science:
- Condensed matter physics
- Topological materials
- Quantum transport
Background:
- Two-terminal conductance quantization in 2D topological systems is experimentally observed.
- Landauer-Buttiker (LB) theory typically explains this, assuming single-channel leads and perfect contacts.
Purpose of the Study:
- To examine the validity of single-channel leads and perfect contact assumptions in LB theory.
- To investigate the microscopic origins of conductance quantization in Chern insulators.
Main Methods:
- Utilized a microscopic model of a Chern insulator connected to leads.
- Employed the nonequilibrium Green's function formalism for numerical analysis.
Main Results:
- Demonstrated perfect quantization of two-terminal conductance numerically.
- Observed highly localized charge current patterns within the leads.
- Found that currents enter and exit the insulator specifically near the corners.
- Showed that single-channel behavior with perfect contact is an emergent property.
Conclusions:
- The study provides numerical evidence justifying the assumptions of the Landauer-Buttiker theory.
- Emergent single-channel behavior and localized currents validate the LB theory for Chern insulators.
- Quantized conductance exhibits dependence on system size and reservoir coupling.
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