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arXiv · 2010.00183

Quantized critical supercurrent in SrTiO$_3$-based quantum point contacts

Evgeny Mikheev·Ilan T. Rosen·David Goldhaber-Gordon
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Abstract

Superconductivity in SrTiO$_3$ occurs at remarkably low carrier densities and therefore, unlike conventional superconductors, can be controlled by electrostatic gates. Here we demonstrate nanoscale weak links connecting superconducting leads, all within a single material, SrTiO$_3$. Ionic liquid gating accumulates carriers in the leads, and local electrostatic gates are tuned to open the weak link. These devices behave as superconducting quantum point contacts with a quantized critical supercurrent. This is a milestone towards establishing SrTiO$_3$ as a single-material platform for mesoscopic superconducting transport experiments, that also intrinsically contains the necessary ingredients to engineer topological superconductivity

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Evgeny Mikheev, Ilan T. Rosen, David Goldhaber-Gordon. 2020-10-01. Quantized critical supercurrent in SrTiO$_3$-based quantum point contacts. https://doi.org/10.1126/sciadv.abi6520

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