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Title: Investigation of the Critical Currents in Thin-Film MoGe Devices
We report on flux-flow properties of 50 nmthick thinfilm amorphous MoGe bridges of different sizes with and without patterned sub-micron holes with different diameters and spacings. Characterization of the devices was carried out in liquid He at 4.2 K in a magnetic field, H, applied perpendicular to the device plane. Two critical currents, Ic1 and Ic2, were studied. The current Ic1 is identified as the onset of a low-resistance state, whereas Ic2 is the current at which the device switches to a high-resistance state, and the corresponding dependences Ic1(H) and Ic2(H) were determined. In the absence of the holes, Ic1 decreases monotonically with H, whereas Ic2(H) manifests lobes resembling those in the Fraunhofer-like pattern characteristic of Josephson junctions. This behavior may be due to formation of an ordered vortex lattice in some current and field ranges. Introducing the hole-line arrays modifies both Ic1(H) and Ic2(H) in a way that is most complicated for larger hole diameters.  more » « less
Award ID(s):
1905742
PAR ID:
10491290
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Institute for Electrical and Electronic Engineers
Date Published:
Journal Name:
IEEE Transactions on Applied Superconductivity
Volume:
34
Issue:
3
ISSN:
1051-8223
Page Range / eLocation ID:
1 to 4
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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