Supercurrent transport through 1e -periodic full-shell Coulomb islands
We experimentally investigate supercurrent through Coulomb islands, where island and leads are fabricated from semiconducting nanowires with fully surrounding superconducting shells. Applying flux along the wire yields a series of destructive Little-Parks lobes with reentrant supercurrent. We find Coulomb blockade with 2e peak spacing in the zeroth lobe and 1e average spacing, with regions of sign