Flux-line shear through narrow constraints in superconducting films

Pruymboom, A.; Kes, P.H.; Drift, E. van der; Radelaar, S.

doi:10.1103/physrevlett.60.1430

Cited by 105 publications

(84 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Finally, it is worth to note that these pinning effects when the vortex lattice matches the line width have also been observed in experiments performed in NbN/Nb 3 Ge bilayers with weak-pinning channels. 13 In this case the matching effects are observed when the vortex motion is along these very weak pinning channels. In our case the matching effects are observed for currents applied parallel to the channels and vortex motion perpendicular to them.…”

mentioning

confidence: 91%

Anisotropic pinning enhancement in Nb films with arrays of submicrometric Ni lines

Jaque

González

Martín

et al. 2002

Applied Physics Letters

View full text Add to dashboard Cite

Arrays of submicrometric Ni lines have been fabricated in superconducting Nb films by electron beam lithography. In the mixed state, these arrays induce strong anisotropy in the dissipation behavior. The dissipation is reduced several orders of magnitude, in the whole applied magnetic field range, when the vortex motion is perpendicular to the Ni lines ͑applied current parallel to them͒ in comparison with dissipation of vortices moving parallel to the lines. In addition, for the samples studied in this work, a change in the slope of the (B) curves is observed when the vortices move perpendicular to the lines and the vortex lattice parameter matches the width of the Ni lines.

show abstract

mentioning

confidence: 91%

Anisotropic pinning enhancement in Nb films with arrays of submicrometric Ni lines

Jaque

González

Martín

et al. 2002

Applied Physics Letters

View full text Add to dashboard Cite

show abstract

“…Additionally the problem we deal with could also be of interest in nanoscale wires. Flux-line-lattice flow has been studied in a novel superconducting devices containing straight, nanometer-scale, weak-pinning channels in a strong-pinning environment [24]. By introducing a constriction into the weak-pinning channels many features of the model we propose can be investigated experimentally.…”

Section: Introductionmentioning

confidence: 99%

Pinning and depinning of a classic quasi-one-dimensional Wigner crystal in the presence of a constriction

Piacente

Peeters

2005

Phys. Rev. B

View full text Add to dashboard Cite

We studied the dynamics of a quasi-one-dimensional chain-like system of charged particles at low temperature, interacting through a screened Coulomb potential in the presence of a local constriction. The response of the system when an external electric field is applied was investigated. We performed Langevin molecular dynamics simulations for different values of the driving force and for different temperatures. We found that the friction together with the constriction pins the particles up to a critical value of the driving force. The system can depin elastically or quasi-elastically depending on the strength of the constriction. The elastic (quasi-elastic) depinning is characterized by a critical exponent β ∼ 0.66 (β ∼ 0.95). The dc conductivity is zero in the pinned regime, it has non-ohmic characteristics after the activation of the motion and then it is constant. Furthermore, the dependence of the conductivity with temperature and strength of the constriction was investigated in detail. We found interesting differences between the single and the multi-chain regimes as the temperature is increased.

show abstract

“…In our structures, the potential asymmetries arise from differences in the interaction strength between vortices and the channel walls, resulting in a substantial ratchet effect for the motion of vortices through the channels. Our design is related to a previous vortex ratchet proposal [8], although our ratchet is in a somewhat different parameter regime.Nanoscale channels for guiding vortices through superconducting films with a minimal influence from pin- ning have been developed for studies of vortex matter in confined geometries, including experiments on melting [9], commensurability [10], and mode locking [11]. Such channels are fabricated from bilayer films of amorphousNbGe, an extremely weak-pinning superconductor, and NbN, with relatively strong pinning.…”

mentioning

confidence: 99%

“…Nanoscale channels for guiding vortices through superconducting films with a minimal influence from pin- ning have been developed for studies of vortex matter in confined geometries, including experiments on melting [9], commensurability [10], and mode locking [11]. Such channels are fabricated from bilayer films of amorphousNbGe, an extremely weak-pinning superconductor, and NbN, with relatively strong pinning.…”

mentioning

confidence: 99%

Asymmetric weak-pinning superconducting channels: Vortex ratchets

Heitmann

Song

et al. 2007

Phys. Rev. B

Self Cite

View full text Add to dashboard Cite

The controlled motion of objects through narrow channels is important in many fields. We have fabricated asymmetric weak-pinning channels in a superconducting thin-film strip for controlling the dynamics of vortices. The lack of pinning allows the vortices to move through the channels with the dominant interaction determined by the shape of the channel walls. We present measurements of vortex dynamics in the channels and compare these with similar measurements on a set of uniformwidth channels. While the uniform-width channels exhibit a symmetric response for both directions through the channel, the vortex motion through the asymmetric channels is quite different, with substantial asymmetries in both the static depinning and dynamic flux flow. This vortex ratchet effect has a rich dependence on magnetic field and driving force amplitude.PACS numbers: 74.25. Qt, 74.25.Sv, 74.25.Op Recently there has been much interest in developing artificial ratchets for generating directed motion using tailored asymmetries [1]. Such ratchets could be used as pathways for producing net transport of matter at the nanoscale. In addition, artificial ratchets can serve as model systems for understanding similar ratchet phenomena in biological systems while allowing for experimental control over many of the ratchet parameters [2]. A variety of ratchets have been considered, but one particular type that has been implemented in several different systems is the rocking ratchet, where a spatial asymmetry is engineered into the potential energy landscape governing particle motion and an external control variable can be adjusted to tilt this potential. The application of an oscillatory drive of the control variable with zero mean can result in the net motion of particles through the potential because of the different rates for overcoming the barriers in the two directions through the ratchet.Implementations of ratchets in solid-state devices include asymmetric structures of electrostatic gates above a two-dimensional electron gas [3], and arrays of Josephson junctions with asymmetric critical currents [4]. Structures have also been developed for producing a ratchet effect with vortices in superconducting thin films involving either asymmetric arrangements of pinning centers [5,6] or asymmetric magnetic pinning structures [7]. In this Communication, we describe a vortex ratchet using two-dimensional guides to generate asymmetric channels for vortex motion. In our structures, the potential asymmetries arise from differences in the interaction strength between vortices and the channel walls, resulting in a substantial ratchet effect for the motion of vortices through the channels. Our design is related to a previous vortex ratchet proposal [8], although our ratchet is in a somewhat different parameter regime.Nanoscale channels for guiding vortices through superconducting films with a minimal influence from pin- ning have been developed for studies of vortex matter in confined geometries, including experiments on melting [9], commensurabili...

show abstract

Flux-line shear through narrow constraints in superconducting films

Cited by 105 publications

References 7 publications

Anisotropic pinning enhancement in Nb films with arrays of submicrometric Ni lines

Anisotropic pinning enhancement in Nb films with arrays of submicrometric Ni lines

Pinning and depinning of a classic quasi-one-dimensional Wigner crystal in the presence of a constriction

Asymmetric weak-pinning superconducting channels: Vortex ratchets

Contact Info

Product

Resources

About