Anisotropy in the Transport Properties of Type II Superconducting Films with Periodic Pinning

Verga, Lucas Garcia; Silva, M. C. Da; Simões, Rafael Plana; Mello, Denise Fernandes de; Venegas, P. A.

doi:10.1007/s10948-012-1763-2

Cited by 5 publications

(5 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Furthermore, it is possible to see well defined anisotropic behavior in the critical forces, mainly for the peaks at B/B ϕ =1/3, 1/2, and 2/3. Anisotropic behavior was previously observed in experimental and theoretical for infinite films, but for higher magnetic fields and different system parameters [13][14][15][16]19,21 . Our simulations also show that, in general, F c y > F c x for fractional matching fields, with the exception of B/B ϕ =1/3.…”

mentioning

confidence: 86%

Critical Forces at Fractional Matching Fields in Superconducting Thin Films with Triangular Pinning Lattice

et al. 2017

View full text Add to dashboard Cite

We numerically study the commensurability effects in the critical forces in a type II superconducting thin film with vortices under the influence of a triangular pinning lattice at sub matching fields and zero temperature. The analysis is made applying a transport force in two mutually perpendicular directions and magnetic field perpendicular to the film surface. The results show critical force peaks at fractional matching fields, as a direct consequence of the commensurability effects. For the first time, we simulate the sequence of force peaks detected in recent experiments. Anisotropic effects in the critical forces are also reported, in analogy with that found at higher fields.

show abstract

mentioning

confidence: 86%

Critical Forces at Fractional Matching Fields in Superconducting Thin Films with Triangular Pinning Lattice

et al. 2017

View full text Add to dashboard Cite

show abstract

“…In particular, for periodic pinning as, for example, square [12][13][14][15]35], triangular [3][4][5][6][7][34][35][36][37], rectangular [1,22,28], honeycomb [2,3,8,29,33] and Kagomé [2,3,8,[29][30][31][32][33][34][35], it is well accepted that for values of the external magnetic field (B) higher than the first matching field (B φ ), vortices organize themselves in a highly symmetric way that leads to a perfect cancelation of the vortex-vortex interaction, generally forming a pattern which is commensurate with the pinning landscape, leading to pronounced peaks of critical force.…”

Section: Introductionmentioning

confidence: 99%

Commensurability effects in the critical forces of a superconducting film with Kagomé pinning array at submatching fields

et al. 2017

View full text Add to dashboard Cite

Using molecular dynamics simulations, we find the commensurability force peaks in a twodimensional superconducting thin-film with a Kagomé pinning array. A transport force is applied in two mutually perpendicular directions, and the magnetic field is increased up to the first matching field. Usually the condition to have pronounced force peaks in systems with periodic pinning is associated to the rate between the applied magnetic field and the first matching field, it must be an integer or a rational fraction. Here, we show that another condition must be satisfied, the vortex ground state must be ordered. Our calculations show that the pinning size and strength may dramatically change the vortex ground state. Small pinning radius and high values of pinning strength may lead to disordered vortex configurations, which fade the critical force peaks. The critical forces show anisotropic behavior, but the same dependence on pinning strength and radius is observed for both driven force directions. Different to cases where the applied magnetic field is higher than the first matching field, here the depinning process begins with vortices weakly trapped on top of a pinning site and not with interstitial vortices. Our results are in good agreement with recent experimental results.

show abstract

“…A corrugated motion of the vortices between the neighboring pinning rows appears more ordered in the structure factor. Figure 5c shows marked peaks around the central peak with fourfold symmetry, as distinct from the study of Verga et al [60]. This sort of ordering results from the coherent motion of the dimer states.…”

mentioning

confidence: 50%

Strong anisotropic transport of vortices in superconductors

Yetiş

Uluer

2015

Physica Status Solidi (b)

View full text Add to dashboard Cite

Anisotropic transport of multiple vortices is investigated by a numerical simulation method in superconductors with triangular pinning arrays. The results are discussed by means of V(I) curves, structure factor, vortex flows, and velocity noise spectrum. The dynamical phase diagram as a function of the pinning strength is obtained to characterize the motion of the vortices. The results reveal the existence of a strong transport anisotropy when the multiple vortices (dimer state) are driven in two perpendicular directions. The anisotropic behavior is interpreted in terms of the triangular geometry of the pinning arrays and the nature of the competitive interactions of vortices with periodic arrays of the pinning centers. . When an ordered vortex lattice is set in motion by a transport current, its motion gives rise to a finite electrical resistance. A promising way to immobilize the vortices is to introduce artificial pinning centers, which is efficient only in a restricted range of low temperatures and magnetic fields [7].Several efforts have been devoted to stabilize vortex motion by adjusting the pinning parameters [8][9][10][11][12][13]. A rich variety of dynamical phases occurs due to the interaction of vortices with attractive pinning sites which promote disorder on the vortex lattice [14][15][16][17][18][19]. Recent experiments have shown that the vortices could display markedly different configurations, such as multiple or giant vortex states confined in mesoscopic superconducting systems [20][21][22][23][24][25][26]. Strong caging effects result in the formation of complex vortex patterns at the interstitial region of the pinning centers [27][28][29][30]. Composite vortex ordering in the presence of periodic pinning arrays is responsible for the formation of anisotropic behavior [31-33],

show abstract

Anisotropy in the Transport Properties of Type II Superconducting Films with Periodic Pinning

Cited by 5 publications

References 13 publications

Critical Forces at Fractional Matching Fields in Superconducting Thin Films with Triangular Pinning Lattice

Critical Forces at Fractional Matching Fields in Superconducting Thin Films with Triangular Pinning Lattice

Commensurability effects in the critical forces of a superconducting film with Kagomé pinning array at submatching fields

Strong anisotropic transport of vortices in superconductors

Contact Info

Product

Resources

About