Imprinting superconducting vortex footsteps in a magnetic layer.
Local polarization of a magnetic layer, a well-known method for storing information, has found its place in numerous applications such as the popular magnetic drawing board toy or the widespread credit cards and computer hard drives. Here we experimentally show that a similar principle can be applied for imprinting the trajectory of quantum units of flux (vortices), travelling in a superconducting film (Nb), into a soft magnetic layer of permalloy (Py). In full analogy with the magnetic drawing board, vortices act as tiny magnetic scribers leaving a wake of polarized magnetic media in the Py board. The mutual interaction between superconducting vortices and ferromagnetic domains has been investigated by the magneto-optical imaging technique. For thick Py layers, the stripe magnetic domain pattern guides both the smooth magnetic flux penetration as well as the abrupt vortex avalanches in the Nb film. It is however in thin Py layers without stripe domains where superconducting vortices leave the clearest imprints of locally polarized magnetic moment along their paths. In all cases, we observe that the flux is delayed at the border of the magnetic layer. Our findings open the quest for optimizing magnetic recording of superconducting vortex trajectories.
Université de Liège, Département de Physique, Sart Tilman, B-4000, Belgium.
Jérémy
J
Brisbois
Universidade Federal de São Carlos, Departamento de Física, São Carlos, 13565-905 SP, Brazil.
Maycon
M
Motta
Université de Liège, Département de Physique, Sart Tilman, B-4000, Belgium.
Jonathan I
JI
Avila
Université de Liège, Département de Physique, Sart Tilman, B-4000, Belgium.|Université Grenoble Alpes, Institut NEEL, F-38000 Grenoble, France.|CNRS, Institut NEEL, F-38000 Grenoble, France.
Gorky
G
Shaw
Université Grenoble Alpes, Institut NEEL, F-38000 Grenoble, France.|CNRS, Institut NEEL, F-38000 Grenoble, France.
Thibaut
T
Devillers
Université Grenoble Alpes, Institut NEEL, F-38000 Grenoble, France.|CNRS, Institut NEEL, F-38000 Grenoble, France.
Nora M
NM
Dempsey
Université de Liège, Département de Physique, Sart Tilman, B-4000, Belgium.
Savita K P
SK
Veerapandian
Université de Liège, Center for Applied Technology in Microscopy (GREENMAT), Sart Tilman, B-4000, Belgium.
Pierre
P
Colson
Université de Liège, SUPRATECS and Department of Electrical Engineering and Computer Science, Sart Tilman, B-4000, Belgium.
Benoît
B
Vanderheyden
Université de Liège, SUPRATECS and Department of Electrical Engineering and Computer Science, Sart Tilman, B-4000, Belgium.
Philippe
P
Vanderbemden
Universidade Federal de São Carlos, Departamento de Física, São Carlos, 13565-905 SP, Brazil.
Wilson A
WA
Ortiz
Université de Liège, Département de Physique, Sart Tilman, B-4000, Belgium.
Ngoc Duy
ND
Nguyen
Université Grenoble Alpes, Institut NEEL, F-38000 Grenoble, France.|CNRS, Institut NEEL, F-38000 Grenoble, France.
Roman B G
RB
Kramer
Université de Liège, Département de Physique, Sart Tilman, B-4000, Belgium.
Alejandro V
AV
Silhanek