Related papers: Thin superconducting disk with B-dependent Jc: Flu…
The vortex contribution to the dc field (H) dependent microwave surface impedance Z_s = R_s+iX_s of YBa_2Cu_3O_{7-x} thin films was measured using suspended patterned resonators. Z_s(H) is shown to be a direct measure of the flux density…
Superconducting transitions are driven by thermal fluctuations close to the transition temperature, Tc. These fluctuations are averaged out in global measurements, leaving imprints on susceptibility and resistance measurements. Here, we use…
Analytical expressions for the evaluation of AC losses in a superconductor-metal composite strip in a nonuniform AC magnetic field having the form of a standing wave are derived. The considered configuration models superconducting tapes,…
The stability against quench is one of the main issue to be pursued in a superconducting material which should be able to perform at very high levels of current densities. Here we focus on the connection between the critical current $I_c$…
The dynamics of magnetic flux distributions across a YBaCuO strip carrying transport current is measured using magneto-optical imaging at 20 K. The current is applied in pulses of 40-5000 ms duration and magnitude close to the critical one,…
Coarse-grained flux density profiles in type-II superconductors with non-parallel vortex configurations are obtained by a proposed phenomenological least action principle. We introduce a functional $C[H(x)]$, which is minimized under a…
Key questions for any superconductor include: what is its maximum dissipation-free electrical current (its `critical current') and can this be used to extract fundamental thermodynamic parameters? Present models focus on depinning of…
Numerical studies of the flux creep in superconductors show that the distribution of the magnetic field at any stage of the creep process can be well described by the condition of spatial constancy of the activation energy $U$ independently…
Superconductors used in magnet technology could carry extreme currents because of their ability to keep the magnetic flux motionless. The dynamics of the magnetic flux interaction with superconductors is controlled by this property. The…
We demonstrate experimentally that the critical current in superconducting NbTiN wires is dependent on their geometrical shape, due to current-crowding effects. Geometric patterns such as 90 degree corners and sudden expansions of wire…
Josephson junctions made of conventional superconductors display Fraunhofer-like oscillations of the critical current as a function of the threaded magnetic flux. When the superconductors are deposited on the surface of a three-dimensional…
We present the current-density functional theory for the superconductor immersed in the magnetic field. The order parameter of the superconducting state, transverse component of the paramagnetic current-density, and electron density are…
Temperature dependence of the zero-field critical current density, Jc0(T), in the CuO2 planes has been investigated for c-axis oriented YBa2Cu3O7-d (Y123) thin films with different hole content, p. p-values were varied by changing the…
A thin flat superconductor of arbitrary shape and with arbitrary in-plane and out-of-plane anisotropy of flux-line pinning is considered, in an external magnetic field normal to its plane. It is shown that the general three-dimensional…
The temperature and field dependence of harmonics in voltage $V_n=V'_n-iV"_n$ using the screening technique have been measured for $\mathrm{Y}\mathrm{Ba}_{2}\mathrm{Cu}_3\mathrm{O}_{7-\delta}$ superconducting thin films. Using the Sun model…
We consider the steady-state nonequilibrium behavior of mesoscopic superconducting wires connected to normal-metal reservoirs. Going beyond the diffusive limit, we utilize the quasiclassical theory and perform a self-consistent calculation…
The flux penetration near a semicircular indentation at the edge of a thin superconducting strip placed in a transverse magnetic field is investigated. The flux front distortion due to the indentation is calculated numerically by solving…
A simple one dimensional model to simulate the establishment of the Bean critical state is introduced. It is shown that the dynamics of the flux lines as they enter the superconductor are dominated by `avalanches'. The distribution of…
Analytic expressions for alternating current (ac) loss in radially arranged superconducting strips are presented. We adopt the weight-function approach to obtain the field distributions in the critical state model, and we have developed an…
The effects of hole content (p) and oxygen deficiency (delta) on the zero-field critical current density, Jc0, were investigated for high-quality c-axis oriented Y1-xCaxBa2Cu3O7-delta (x = 0, 0.05, 0.10, and 0.20) thin films. Ca was used to…