Local control of parity and charge in nanoscale superconducting lead islands

2025/07/16 by Stefano Trivini, Trivini, Stefano, Jon Ortuzar +9 · 1 citation
Chemistry · Physics and Astronomy · #FOS: Physical sciences #Inorganic Fluorides and Related Compounds #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Physics of Superconductivity and Magnetism #Superconductivity in MgB2 and Alloys

paper · pdf · doi:10.48550/arxiv.2507.12150

openalex publication_date 2025/07/16 · openalex created_date 2025/10/14 · openalex updated_date 2026/07/28

Abstract

Small superconducting islands can exhibit charge quantization, where Coulomb interactions compete with Cooper pairing. Using scanning tunneling spectroscopy, we probe this interplay by measuring the charging energy (E_C) and the pairing energy (Δ) of individual nano-islands. Below a critical island size, where E_C > Δ, we observe a crossover between even and odd parity ground states. By applying controlled voltage pulses, we continuously tune the island's electrostatic potential and map the full charge-parity landscape. These results demonstrate tunable superconducting ground states, offering a potential platform for qubit design and control.

Citations

• From local to collective superconductivity in proximitized graphene
• Observation of Yu-Shiba-Rusinov states in superconducting graphene
• Electric Field Effect in Atomically Thin Carbon Films
• Coulomb blockade of single-electron tunneling, and coherent oscillations in small tunnel junctions
• Theory of dirty superconductors

Cited by

• Imaging asymmetric Coulomb blockade phenomena across metallic nanoislands

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