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arXiv · 0808.1723

Corner Junction as a Probe of Helical Edge States

Chang-Yu Hou·Eun-Ah Kim·Claudio Chamon
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Abstract

We propose and analyze inter-edge tunneling in a quantum spin Hall corner junction as a means to probe the helical nature of the edge states. We show that electron-electron interactions in the one-dimensional helical edge states result in Luttinger parameters for spin and charge that are intertwined, and thus rather different than those for a quantum wire with spin rotation invariance. Consequently, we find that the four-terminal conductance in a corner junction has a distinctive form that could be used as evidence for the helical nature of the edge states.

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Chang-Yu Hou, Eun-Ah Kim, Claudio Chamon. 2008-08-13. Corner Junction as a Probe of Helical Edge States. https://doi.org/10.1103/physrevlett.102.076602

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