[en] The superconducting critical current of corner-shaped Al superconducting microstrips has been investigated. We demonstrate that the sharp turns lead to asymmetric vortex dynamics, allowing for easier penetration from the inner concave angle than from the outer convex angle. This effect is evidenced by a rectification of the voltage signal otherwise absent in straight superconducting strips. At low magnetic fields, an enhancement of the critical current with increasing magnetic field is observed for a particular combination of field and current polarity, confirming a theoretically predicted competing interplay of superconducting screening currents and applied currents at the inner side of the turn.
Disciplines :
Physics
Author, co-author :
Adami, Obaïd-Allah ; Université de Liège - ULiège > Département de physique > Physique de la matière condensée
Cerbu, Dorin; Katholieke Universiteit Leuven - KUL
Cabosart, Damien; Université Catholique de Louvain - UCL
Motta, Maycon; Federal University of San Carlos
Cuppens, Jo; Katholieke Universiteit Leuven - KUL
Ortiz, Wilson Aires; Federal University of San Carlos
Moshchalkov, Wilson Aires; Katholieke Universiteit Leuven - KUL
Hackens, Benoît; Université Catholique de Louvain - UCL
Delamare, Romain; Université Catholique de Louvain - UCL
Van de Vondel, Joris; Katholieke Universiteit Leuven - KUL
Silhanek, Alejandro ; Université de Liège - ULiège > Département de physique > Physique de la matière condensée
Language :
English
Title :
Current crowding effects in superconducting corner-shaped Al microstrips
Publication date :
06 February 2013
Journal title :
Applied Physics Letters
ISSN :
0003-6951
eISSN :
1077-3118
Publisher :
American Institute of Physics, Melville, United States - New York
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