TY  - JOUR
AU  - Womack, F. N.
AU  - Adams, P. W.
AU  - Valles, J. M.
AU  - Catelani, Gianluigi
TI  - Critical field behavior of a multiply connected superconductor in a tilted magnetic field
JO  - Physical review / B
VL  - 100
IS  - 17
SN  - 2469-9950
CY  - Woodbury, NY
PB  - Inst.
M1  - FZJ-2019-05367
SP  - 174505
PY  - 2019
AB  - We report magnetotransport measurements of the critical field behavior of thin Al films deposited onto multiply connected substrates. The substrates were fabricated via a standard electrochemical process that produced a triangular array of 66-nm-diameter holes having a lattice constant of 100 nm. The critical field transition of the Al films was measured near Tc as a function of field orientation relative to the substrate normal. With the field oriented along the normal (θ=0), we observe reentrant superconductivity at a characteristic matching field Hm=0.22 T, corresponding to one flux quantum per hole. In tilted fields, the position H∗ of the reentrance feature increases as sec(θ), but the resistivity traces are somewhat more complex than those of a continuous superconducting film. We show that when the tilt angle is tuned such that H∗ is of the order of the upper critical field Hc, the entire critical region is dominated by the enhanced dissipation associated with a submatching perpendicular component of the applied field. At higher tilt angles a local maximum in the critical field is observed when the perpendicular component of the field is equal to the matching field.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000495041000002
DO  - DOI:10.1103/PhysRevB.100.174505
UR  - https://juser.fz-juelich.de/record/866196
ER  -