Related papers: Where does the transport current flow in Bi2Sr2CaC…
Transverse ac permeability measurements in Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta }$ single crystals at low fields and temperatures in a vortex configuration free of external forces show that the decrease of the critical current as measured by…
We investigated vortex dynamics in a single-crystal sample of type-II superconductor NbSe$_{2}$ using scanning tunneling microscopy at 4.2 K. The decay of the magnetic field at a few nT/s in our superconducting magnet induced the…
Measurement of the free flux flow resistance in monocrystalline highly anisotropic BSCCO reveals a low field magneto-resistive effect nearly 100 times that expected from a naive application of the Bardeen-Stephen rule R/Rn = B/Bc2.…
The current distribution across the thickness of a current-carrying rectangular film in the Meissner state was established long ago by the London brothers. The distribution across the width is more complicated but was later shown to be…
To investigate the dynamics of driven vortices in superconductors, noise in the local vortex density was investigated in the mixed state of a high-$T_c$ superconductor, Bi$_2$Sr$_2$CaCu$_2$O$_y$, using a two-dimensional electron gas (2DEG)…
Electrical transport measurements using a multiterminal configuration are presented, which prove that in BSCCO single crystals near the transition temperature in zero external magnetic field the secondary voltage is induced by thermally…
The flux lines dynamics have been investigated on MgB2 bulk superconductors obtained by reactive liquid infiltration by measuring the ac magnetic susceptibility. The fundamental and third harmonics have been studied as a function of…
We present results for the in-plane resistivity as a function of temperature for clean single crystal samples of BSCCO-2212 in applied magnetic fields above 0.5 T. Several fixed angles between the magnetic field and the crystal c-axis were…
In the mixed state of type II superconductors, vortices penetrate the sample and form a correlated system due to the screening of supercurrents around them. Interestingly, we can study this correlated system as a function of density and…
The effect of fractal clusters on magnetic and transport properties of percolative superconductors is considered. The superconductor contains percolative superconducting cluster, carrying a transport current, as well as clusters of a normal…
A new class of artificial atoms, such as synthetic nanocrystals or vortices in superconductors, naturally self-assemble into ordered arrays. This property makes them applicable to the design of novel solids, and devices whose properties…
We explore the experimental implications of a recent theory of the quantum dynamics of vortices in two-dimensional superfluids proximate to Mott insulators. The theory predicts modulations in the local density of states in the regions over…
Four regimes of vortex motion were identified in the magnetoresistance of Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ single crystals: (1) thermally activated flux flow (TAFF) in samples with surface defects caused by thermal annealing; (2)…
We explore the experimental implications of a recent theory of the quantum dynamics of vortices in superfluids proximate to Mott insulators (cond-mat/0408329 and cond-mat/0409470). The theory predicts modulations in the local density of…
We report measurements of the magnetic penetration depth \lambda_m(T) in the presence of a DC magnetic field in optimally doped BSCCO-2212 single crystals. Warming, after magnetic field is applied to a zero-field cooled sample, results in a…
The existence of a peak effect in transport properties (a maximum of the critical current as function of magnetic field) is a well-known but still intriguing feature of type II superconductors such as NbSe2 and Bi-2212. Using a model of…
The critical current density of four MgB2 samples was measured inductively and for one of them also by transport. Pure phased and dense bulk samples yield a critical current density which in value, as well as in its magnetic field and…
Using high sensitivity magneto-optical imaging we find evidence for a jump in local vortex density associated with a vortex liquid to solid phase transition just above the lower critical field in a single crystal of Bi2Sr2CaCu2O8. We find…
Scanning Hall probe and local Hall magnetometry measurements have been used to investigate flux distributions in large mesoscopic superconducting disks with sizes that lie near the crossover between the bulk and mesoscopic vortex regimes.…
The influence of fractal clusters of a normal phase on distinctive features of current-voltage characteristic of percolative type-II superconductors is considered. The results of high-resolution measurements of the differential resistance…