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arXiv · 1902.05516

Quantized conductance through a spin-selective atomic point contact

Martin Lebrat·Samuel Häusler·Philipp Fabritius·Dominik Husmann·Laura Corman·Tilman Esslinger
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Abstract

We implement a microscopic spin filter for cold fermionic atoms in a quantum point contact (QPC) and create fully spin-polarized currents while retaining conductance quantization. Key to our scheme is a near-resonant optical tweezer inducing a large effective Zeeman shift inside the QPC while its local character limits dissipation. We observe a renormalization of this shift due to interactions of a few atoms in the QPC. Our work represents the analog of an actual spintronic device and paves the way to studying the interplay between spin-splitting and interactions far from equilibrium.

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Martin Lebrat, Samuel Häusler, Philipp Fabritius, Dominik Husmann, Laura Corman, Tilman Esslinger. 2019-02-14. Quantized conductance through a spin-selective atomic point contact. https://doi.org/10.1103/physrevlett.123.193605

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