Related papers: Flux trapping in NbTiN strips
The magnetoresistance of ultrathin insulating films of Bi has been studied with magnetic fields applied parallel and perpendicular to the plane of the sample. Deep in the strongly localized regime, the magnetoresistance is negative and…
Superconducting Quantum Interference Devices (SQUIDs) can have excellent spin sensitivity depending on their magnetic flux noise, pick-up loop diameter, and distance from the sample. We report a family of scanning SQUID susceptometers with…
We investigate the origin of matching effect observed in disordered superconducting NbN thin films with periodic array of holes. In addition to the periodic variation in the electrical resistance just above the superconducting transition…
Magnetic flux trapping in the Meissner transition of superconducting radio frequency cavities can substantially increase dissipation which impacts cryogenic costs and necessitates expensive magnetic shielding. Recent findings point at the…
Nb films containing extended arrays of holes with 45-nm diameter and 100-nm spacing have been fabricated using anodized aluminum oxide (AAO) as substrate. Pronounced matching effects in the magnetization and Little-Parks oscillations of the…
In superconducting thin films, engineered lattice of antidots (holes) act as an array of columnar pinning sites for the vortices and thus lead to vortex matching phenomena at commensurate fields guided by the lattice spacing. The strength…
The magnetoresistance of thin superconducting strips subject to a perpendicular magnetic field B and low temperatures T manifests a sequence of alternating superconductor-insulator transitions (SIT). We study this phenomenon within a quasi…
We investigate the phenomenon of the decay of a supercurrent due to the zero-temperature quantum tunneling of vortices from the edge in a thin superconducting film in the absence of an external magnetic field. An explicit formula is derived…
Magnetic fields penetrate a type-II superconductor as magnetic flux quanta, called vortices. In a clean superconductor they arrange in a hexagonal lattice, while by adding periodic artificial pinning centers many other arrangements can be…
Direct observation of vortices by the scanning SQUID microscopy was made on large mesoscopic disks of an amorphous MoGe thin film. Owing to the weak pinning nature of the amorphous film, vortices are able to form geometry induced,…
Superconducting quantum interference device (SQUID) microscopy shows stripes of increased diamagnetic susceptibility in underdoped, but not overdoped, single crystals of Ba(Fe1-xCox)2As2. These stripes of increased diamagnetic…
We study vortex current distributions in narrow thin-film superconducting strips. If one defines the vortex core ``boundary" as a curve where the current reaches the depairing value, intriguing features emerge. Our conclusions based on the…
Using an optimally coupled nanometer-scale superconducting quantum interference device, we measure the magnetic flux originating from an individual ferromagnetic Ni nanotube attached to a Si cantilever. At the same time, we detect the…
This paper addresses the problem of vortex formation during a rapid quench in a superconducting film. It builds on previous work showing that in a local gauge theory there are two distinct mechanisms of defect formation, based on…
The penetration of magnetic flux into a thin superconducting film of Nb3Sn with critical temperature 17.8K and critical current density 6MA/cm^2 was visualized using magneto-optical imaging. Below 8 K an avalanche-like flux penetration in…
We observe single vortices as they penetrate the edge of a superconductor using a high-sensitivity magneto-optical microscope. The vortices leap across a gap near the edge, a distance that decreases with increasing applied field and sample…
A scanning superconducting quantum interference device (SQUID) microscope (SSM) is used to study the magnetic imaging of dynamic motion of quantized interlayer vortices induced by the Lorentz force in anisotropic high-Tc…
We suggest a new theoretical approach describing the velocity of magnetic flux dendrite penetration into thin superconducting films. The key assumptions for this approach are based upon experimental observations. We treat a dendrite tip…
We report the direct imaging of a novel modulated flux striped domain phase in a nearly twin-free YBCO crystal. These domains arise from instabilities in the vortex structure within a narrow region of tilted magnetic fields at small angles…
Understanding vortex matter in type-II superconductors is central to controlling dissipation and flux pinning in superconducting materials and devices. Here, we use cryogenic scanning nitrogen vacancy magnetometry (NVM) to image Abrikosov…