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Updated: May 16, 2026

Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
Nonequilibrium transport through a gate-controlled barrier on the quantum spin Hall edge
Roni Ilan1, Jérôme Cayssol, Jens H Bardarson
1Department of Physics, University of California, Berkeley, California 94720, USA.
Abstract:
The quantum spin Hall insulator is characterized by the presence of gapless helical edge states where the spin of the charge carriers is locked to their direction of motion. In order to probe the properties of the edge modes, we propose a design of a tunable quantum impurity realized by a local gate under an external magnetic field. Using the integrability of the impurity model, the conductance is computed for arbitrary interactions, temperatures and voltages, including the effect of Fermi liquid leads. The result can be used to infer the strength of interactions from transport experiments.
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