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arXiv · 2311.11954

Efficient Cooper Pair Splitting Without Interactions

E. S. Tikhonov·V. S. Khrapai
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Abstract

For the three-terminal NSN device with single-mode normal terminals and without Coulomb blockade, we propose the interpretation of charge transfer process which allows us to consistently characterize the device operation as that of a Cooper pair splitter in terms of scattering matrix elements as well as in terms of measurable quantities. The obtained explicit expression for the splitting probability notably contains the two-particle interference term not available from conductance measurements. We show that splitting doesn't necessarily rely on single-particle crossed Andreev reflection amplitude thus allowing for the unit efficiency at zero energy. Our results imply that the current cross-correlator generally doesn't provide definite measure of splitting.

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E. S. Tikhonov, V. S. Khrapai. 2024-08-03. Efficient Cooper Pair Splitting Without Interactions. https://doi.org/10.1103/physrevb.110.075429

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