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DOE OSTI · 1813036

Quantized critical supercurrent in SrTiO 3 -based quantum point contacts

Mikheev, Evgeny·Rosen, Ilan T.·Goldhaber-Gordon, David
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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 toward 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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BibTeXRIS

Mikheev, Evgeny, Rosen, Ilan T., Goldhaber-Gordon, David. 2021-10-01. Quantized critical supercurrent in SrTiO 3 -based quantum point contacts. https://doi.org/10.1126/sciadv.abi6520

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