[en] Flux avalanches are known to occur as a consequence of thermomagnetic instabilities. Some of their fingerprints are jumps in magnetization curves, or a paramagnetic reentrance in AC susceptibility measurements. In this work we have studied flux avalanches triggered by an AC field cycle by means of AC susceptibility and residual magnetization after an applied AC field measured as a function of an AC excitation field (h). These measurements allow comparing both results with magneto-optical imaging carried out in similar conditions. The results show a correspondence for the onset of the avalanche activity, as well as between the residual magnetic moment and the mean gray value calculated from the magneto-optical images in the remanent state.
Disciplines :
Physics
Author, co-author :
Motta, M; Universidade Federal de Sao Carlos, Brazil
Colauto, F; Universidade Federal de Sao Carlos, Brazil
Johansen, TH; University of Oslo - UiO
Dinner, RB; University of Cambridge
Blamire, MG; University of Cambridge
Ataklti, GW; Katholieke Universiteit Leuven - KUL
Moshchalkov, VV; Katholieke Universiteit Leuven - KUL
Silhanek, Alejandro ; Université de Liège - ULiège > Département de physique > Physique de la matière condensée
Ortiz, WA; Universidade Federal de Sao Carlos
Language :
English
Title :
Flux avalanches triggered by AC magnetic fields in superconducting thin films