相关论文: Determination of critical current density from arb…

The phenomenon of superconductivity occurs in the phase space of three principal parameters: temperature T, magnetic field B, and current density Jd . The critical temperature Tc is one of the first parameters that is measured and in a…

We study the quasiparticle energy relaxation processes in superconducting Nb films of different thicknesses corresponding to different electron mean free paths in a state far from equilibrium, that is the highly dissipative flux-flow state…

We present the new paradigm of critical current by design. Analogous to materials by design, it aims at predicting the optimal defect landscape in a superconductor for targeted applications by elucidating the vortex dynamics responsible for…

Superconductors like other solids cannot relax instantaneously from thermally excited (disturbed) states to thermodynamic equilibrium. In this paper, relaxation of a multi-filamentary and of a thin film superconductor from thermal…

The frequency dependent conductance of a two-dimensional quantum wire is computed using a current conserving formalism. The correction to the dc-conductance due to a time-dependent potential is related to the local partial density of states…

Characterizing current fluctuations in a steady state is of fundamental interest and has attracted considerable attention in the recent past. However, the bulk of the studies are limited to systems that either do not exhibit a phase…

Measurement of the current-voltage characteristics of point contacts makes it possible to study the properties of individual crystallites in a superconducting ceramic. The critical current density in the superconducting regions of the…

High critical current density Jc is generally the most important property of any superconductor used for applications. The critical current Ic is most frequently measured by transport 4 probe V-I techniques and the measured Ic is then…

It is shown that the critical temperature of the superconductor is related to the Sommerfeld constant, i.e. it is determined by the Fermi energy for I-type superconductors. The estimation of properties of II-type superconductors reveals a…

We perform a numeric study of the flux transitions in a superconducting ring at fixed temperature, while the applied field is swept at an ideally slow rate. The current around the ring and its free energy are evaluated. We partially explain…

It has been noticed that the critical current density Jc of some of the superconducting samples, calculated on the basis of Bean model, increases with increasing magnetic field H up to a significant range above H=0. This is an inconsistent…

To address unsolved fundamental problems of the intermediate state (IS), the equilibrium magnetic flux structure and the critical field in a high purity type-I superconductor (indium film) are investigated using magneto-optical imaging with…

Recent experiments strongly indicate deep connections between transports of strange metal and high $T_c$ superconductors. For instance, it is known that the dependence of the zero-temperature phase stiffness on the critical superconducting…

Dynamics of the response of type-II superconductors to a time-varying magnetic field can exhibit a rate-independent or rate-dependent hysteresis. An energy dissipation rate in a superconductor placed in a time-varying magnetic field depends…

For any practical superconductor the magnitude of the critical current density, $J_\textrm{c}$, is crucially important. It sets the upper limit for current in the conductor. Usually $J_\textrm{c}$ falls rapidly with increasing external…

Magnetic flux distribution across a high-temperature superconductor strip is measured using magneto-optical imaging at 15 K. Both the current-carrying state and the remanent state after transport current are studied up to the currents 0.97…

Shear relaxation and dynamic density fluctuations are studied within a Rouse model, generalized to include the effects of permanent random crosslinks. We derive an exact correspondence between the static shear viscosity and the resistance…

We study the low temperature dynamics of a single flux line in a bulk type-II superconductor, driven by a surface current, both near and above the onset of an instability which sets in at a critical driving. We found that above the critical…

Terahertz time-domain conductivity measurements in 2 to 100 nm thick iron films resolve the femtosecond time delay between applied electric fields and resulting currents. This response time decreases for thinner metal films. The macroscopic…

We have developed a real-time beam current density meter for charged particle beams. It measures the mean current density by collimating a uniform and large diameter primary beam. The suppression of the secondary electrons and the…