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arXiv · 1003.4316

Cooper-Pair Injection into Quantum Spin Hall Insulators

Koji Sato·Daniel Loss·Yaroslav Tserkovnyak
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Abstract

We theoretically study tunneling of Cooper pairs from a superconductor spanning a two-dimensional topological insulator strip into its helical edge states. The coherent low-energy electron-pair tunneling sets off positive current cross correlations along the edges, which reflect an interplay of two quantumentanglement processes. Most importantly, superconducting spin pairing dictates a Cooper pair partitioning into the helical edge liquids, which transport electrons in opposite directions for opposite spin orientations. At the same time, Luttinger-liquid correlations fractionalize electrons injected at a given edge into counterpropagating charge pulses carrying definite fractions of the elementary electron charge.

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Koji Sato, Daniel Loss, Yaroslav Tserkovnyak. 2010-12-03. Cooper-Pair Injection into Quantum Spin Hall Insulators. https://doi.org/10.1103/physrevlett.105.226401

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