Anodization-free fabrication process for high-quality cross-type Josephson tunnel junctions based on a Nb/Al-AlOx/Nb trilayer

• Verfasst von: Adam, Fabienne [VerfasserIn]
• Verfasst von: Enss, Christian [VerfasserIn]
• Verfasst von: Kempf, Sebastian [VerfasserIn]
• Titel: Anodization-free fabrication process for high-quality cross-type Josephson tunnel junctions based on a Nb/Al-AlOx/Nb trilayer
• Verf.angabe: F Adam, C Enss and S Kempf
• E-Jahr: 2024
• Jahr: 8 July 2024
• Umfang: 12 S.
• Illustrationen: Illustrationen
• Fussnoten: Gesehen am 19.12.2024 ; Im Titel ist der Buchstabe "x" tiefgestellt
• Titel Quelle: Enthalten in: Superconductor science and technology
• Ort Quelle: Bristol : IOP Publ., 1989
• Jahr Quelle: 2024
• Band/Heft Quelle: 37(2024), 8, Artikel-ID 085013, Seite 1-12
• ISSN Quelle: 1361-6668
• DOI: doi:10.1088/1361-6668/ad59cf
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1913044564

Abstract

Josephson tunnel junctions form the basis for various superconductor electronic devices. For this reason, enormous efforts are routinely taken to establish and later on maintain a scalable and reproducible wafer-scale manufacturing process for high-quality Josephson junctions. Here, we present an anodization-free fabrication process for Nb/Al-AlO x /Nb cross-type Josephson junctions that requires only a small number of process steps and that is in general intrinsically compatible with wafer-scale fabrication. We show that the fabricated junctions are of very high quality and, compared to other junction types, exhibit not only a significantly reduced capacitance but also an almost rectangular critical current density profile. Our process hence enables the usage of low capacitance Josephson junctions for superconductor electronic devices such as ultra-low noise dc-superconducting quantum interference devices (SQUIDs), microwave SQUID multiplexers based on non-hysteretic rf-SQUIDs and RFSQ circuits.