Naslov
Current transfer and initial dissipation in high-Tc superconductors

Autori
Prester, Mladen

Izvornik
Superconductor science and technology (0953-2048) 11 (1998), 4; 333-357

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, pregledni rad, znanstveni

Ključne riječi
superconductivity; high temperature superconductors; critical currents; weak link networks; Josephson junction; percolation;

Sažetak
Various aspects of the problem of current transfer in high-Tc superconductors (HTS) are reviewed. The spatial inhomogeneities of various types are identified as a primary cause of non-uniformity of both normal and super-currents in real samples of HTS. The role these inhomogeneities play in transport features of the samples is discussed. The case of grain boundaries in polycrystalline samples is elaborated in detail. The local structural and transport properties of isolated grain boundaries were first reviewed and then integrated into the knowledge of global (macroscopic) charge transport. The paper emphasises the common ingredients characterising the transport in various forms and families of HTS samples in small magnetic fields. The phenomenon of percolation is identified as the most obvious one and is shown to dominate a large number of observations covered by this report. The experimental results focused by this report elaborate primarily the problems of critical currents, initial dissipation and current-voltage characteristics, penetration depth, resistive and metal-insulator transition, resistance noise and magneto-optical studies of current paths. Various models for current transfer (disordered-bonds, brick-wall and railway-switch) are also reviewed and discussed.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

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