| Full text | |
| Author(s): Show less - |
Motta, M.
[1]
;
Burger, L.
[2]
;
Jiang, Lu
[3]
;
Acosta, J. D. Gonzalez
[4, 5]
;
Jelic, Z. L.
[5, 6]
;
Colauto, F.
[1]
;
Ortiz, W. A.
[1]
;
Johansen, T. H.
[7]
;
Milosevic, V, M.
;
Cirillo, C.
[8]
;
Attanasio, C.
[9, 8]
;
Xue, Cun
[10, 11]
;
Silhanek, V, A.
;
Vanderheyden, B.
[2]
Total Authors: 14
|
| Affiliation: Show less - | [1] Univ Fed Sao Carlos, Dept Fis, BR-13565905 Sao Carlos, SP - Brazil
[2] Univ Liege, Dept Elect Engn & Comp Sci, Montefiore Res Unit, B-4000 Sart Tilman Par Liege - Belgium
[3] Northwestern Polytech Univ, Sch Aeronaut, Xian 710072 - Peoples R China
[4] Univ Magdalena, Fac Ingn, Santa Marta - Colombia
[5] V, Univ Antwerp, Dept Fys, Groenenborgerlaan 171, B-2020 Antwerp - Belgium
[6] Nokia Bell Labs, Antwerp - Belgium
[7] Univ Oslo, Dept Phys, POB 1048, N-0316 Oslo - Norway
[8] Univ Salerno, CNR SPIN, I-84084 Fisciano, SA - Italy
[9] Univ Salerno, Dipartimento Fis ER Caianiello, I-84084 Fisciano, Sa - Italy
[10] Northwestern Polytech Univ, Sch Mech Civil Engn & Architecture, Xian 710072 - Peoples R China
[11] Northwestern Polytech Univ, MIIT Key Lab Dynam & Control Complex Syst, Xian 710072 - Peoples R China
Total Affiliations: 11
|
| Document type: | Journal article |
| Source: | Physical Review B; v. 103, n. 22 JUN 9 2021. |
| Web of Science Citations: | 1 |
| Abstract | |
Considering a noncentrosymmetric pinning texture composed of a square array of triangular holes, the magnetic flux penetration and expulsion are investigated experimentally and theoretically. A direct visualization of the magnetic landscape obtained using a magneto-optical technique on a Nb film is complemented by a multiscale numerical modeling. This combined approach allows the magnetic flux dynamics to be identified from the single flux quantum limit up to the macroscopic electromagnetic response. Within the theoretical framework provided by time-dependent Ginzburg-Landau simulations, an estimation of the in-plane current anisotropy is obtained and its dependence with the radius of the curvature of hole vertices is addressed. These simulations show that current crowding plays an important role in channeling the flux motion, favoring hole-to-hole flux hopping rather than promoting interstitial flux displacement in between the holes. The resulting anisotropy of the critical current density gives rise to a distinct pattern of discontinuity lines for increasing and decreasing applied magnetic fields, in sharp contrast to the invariable patterns reported for centrosymmetric pinning potentials. This observation is partially accounted for by the rectification effect, as demonstrated by finite-element modeling. At low temperatures, where magnetic field penetration is dominated by thermomagnetic instabilities, highly directional magnetic flux avalanches with a fingerlike shape are observed to propagate along the easy axis of the pinning potential. This morphology is reproduced by numerical simulations. Our findings demonstrate that anisotropic pinning landscapes and, in particular, ratchet potentials produce subtle modifications to the critical state field profile that are reflected in the distribution of discontinuity lines. (AU) | |
| FAPESP's process: | 07/08072-0 - Fundamental research in superconductivity and magnetism - systems potentially useful for aplications: advanced oxides and superconductors patterned with artificial structures |
| Grantee: | Wilson Aires Ortiz |
| Support Opportunities: | Research Projects - Thematic Grants |
| FAPESP's process: | 09/10818-5 - Interaction of Vortex Matter with structures of uncorrelated defects - Harmonic Susceptibility, Magneto-optical Imaging and Micro-Hall sensing |
| Grantee: | Maycon Motta |
| Support Opportunities: | Scholarships in Brazil - Doctorate |