KIT | KIT-Bibliothek | Impressum | Datenschutz

Onset of phase diffusion in high kinetic inductance granular aluminum micro-SQUIDs

Friedrich, Felix; Winkel, Patrick; Borisov, Kiril; Seeger, Hannes; Sürgers, Christoph; Pop, Ioan M; Wernsdorfer, Wolfgang

Abstract (englisch):
Superconducting granular aluminum is attracting increasing interest due to its high kinetic inductance and low dissipation, favoring its use in kinetic inductance particle detectors, superconducting resonators or quantum bits. We perform switching current measurements on DC-SQUIDs, obtained by introducing two identical geometric constrictions in granular aluminum rings of various normal-state resistivities in the range from ρ n = 250–5550 μΩ cm. The relative high kinetic inductance of the SQUID loop, in the range of tens of nH, leads to a suppression of the modulation in the measured switching current versus magnetic flux, accompanied by a distortion towards a triangular shape. We observe a change in the temperature dependence of the switching current histograms with increasing normal-state film resistivity. This behavior suggests the onset of a diffusive motion of the superconducting phase across the constrictions in the two-dimensional washboard potential of the SQUIDs, which could be caused by a change of the local electromagnetic environment of films with increasing normal-state resistivities.

Open Access Logo


Verlagsausgabe §
DOI: 10.5445/IR/1000099480
Veröffentlicht am 31.10.2019
Cover der Publikation
Zugehörige Institution(en) am KIT Physikalisches Institut (PHI)
Institut für Nanotechnologie (INT)
Publikationstyp Zeitschriftenaufsatz
Publikationsmonat/-jahr 12.2019
Sprache Englisch
Identifikator ISSN: 0953-2048, 1361-6668
KITopen-ID: 1000099480
HGF-Programm 43.21.02 (POF III, LK 01)
Quantum Properties of Nanostructures
Erschienen in Superconductor science and technology
Band 32
Heft 12
Seiten 125008
Vorab online veröffentlicht am 31.10.2019
Nachgewiesen in Web of Science
Scopus
KIT – Die Forschungsuniversität in der Helmholtz-Gemeinschaft
KITopen Landing Page