These Proceedings of a NATO-ARW (HTECH ARW 96 00 52) held at the International Center for Theoretical Physics, Trieste, Italy from Aug 5 till Aug 9, 1996 resulted from many discussions between various workers, concerning the need for a gathering of all (if possible) who were concerned about the subject of superconductivity fluctuations in High critical Temperature Superconductors (HTS). It appeared to many that the Skocpol-Tinkham work of 1975 had to be revitalized in view of the discovery of the new superconducting ceramics and the enormous amount of work having already taken place. The study of HTS is one of the most prominent research subject in solid state sciences. The understanding of the role of fluctuations is also thought to be necessary before technological applications since the fluctuations may destroy the superconducting state. The workshop discussions have touched upon (i) Superconducting fluctuations in the vicinity of the critical transition, (ii) Superconductivity fluctuations near the percolation transition, and (iii) Fluctuations of the vortex lattice at the lattice melting temperature. These topics served as initiators for a very great amount of discussions with many comments from the audience. More than forty "long lectures" and two "poster sessions" were held. Private discussions going unrecorded but obviously took place at many locations : lecture halls, staircases, cafetaria, bedrooms, bars, beach, . . .

Klappentext

The study of high critical temperature superconductors (HTS) is one of the most prominent research subjects in solid state science. An understanding of the role of fluctuations is also believed to be necessary in advance of technological applications, since the fluctuations may destroy the superconducting state. br/ The discussions focus on: (i) superconducting fluctuations in the vicinity of the critical transitions; (ii) superconductivity fluctuations near the percolation transition; and (iii) fluctuations of the vortex lattice at the lattice melting temperature. These topics are all the subject of more or less intense debate. The effects of fluctuations on static properties and on electrical and thermal transport, properties in the emab/em plane and along the emc/em axis, the effect of a magnetic field on phenomena, specifically in layered compounds are still undecided. The effect of a magnetic field is still not clear. Specific fluctuations of the vortex lattice in HTS ceramics as compared to conventional superconductors are still intensely debated. br/ In its clear presentation of the experimental, theoretical and simulation aspects, together with the comprehensive list of references, this compendium is the best to appear in over 20 years.

Inhalt
Fluctuation phenomena in superconductors.- C-axis transport in YBa2Cu3O7-?.- Analysis of the specific heat jump at Tc for SmBa2Cu3O7-?.- Fluctuation conductivity in a-b plane and along c-axis in films of YBaCuO.- Fluctuation thermoelectric effect above the superconducting transition.- Magnetoresistance in HTSC far above Tc: fluctuations versus normal-state contributions.- Electric field effects in high-Tc superconductors.- Effect of fluctuations on the thermal conductivity of High-Tc superconductors.- Fluctuation phenomena in BSCCO (2212) whiskers.- The fluctuation induced pseudogap in the infrared optical conductivity of high temperature superconductors.- Specific heat studies of low dimensional high-Tc superconductors.- d-pairing in high temperature superconductors: pro and contra from the fluctuation phenomena analysis.- Measurements of the frequency dependent microwave fluctuation conductivity of cuprate thin film superconductors.- Fluctuation phenomena in tunnel and Josephson junctions.- The role of density of states fluctuations on the c-axis resistivity of High Tc superconductors.- The effect of disorder on melting and decoupling transitions in layered superconductors.- Vortex line fluctuations and phase transitions in type II superconductors.- Flux lattice melting in the lowest Landau level approximation : results in three dimensions.- Fluctuational contribution to the resistivity in YBa2Cu3O7-? in magnetic fields.- Low field fluctuation magnetoconductivity in Bi2Sr2CaCu2O8 and YBa2Cu3O7 : gaussian, critical, and LLL scalings.- Fluctuation effects in mixed state of type II superconductor.- Two dimensional vortex fluctuations in high Tc superconductors.- Critical vs lowest-Landau-level scaling in the Ginzburg-Landau theory.- Fluctuations in the latticeGinzburg-Landau model.- Superconducting transition induced by columnar disorder in strong magnetic field.- Vortex fluctuations in vortex liquids.- Magnetic field crossover between 2D and 3D regimes of gaussian fluctuations in layered superconductors.- Aspects of the d-wave superconductivity.- Universal critical quantum properties of cuprate superconductors.- Theory of superconducting fluctuations in the strong coupling model.- Fluctuation phenomena in layered superconductors.- Anderson theorem and spatial fluctuations in the gap of disordered superconductors.- Berezinskii-Kosterlitz-Thouless transition in two-dimensional XXZ easy-plane quantum Heisenberg magnets.- Pairing symmetry and pairing interactions in the cuprates.- Superconducting properties of Nb/CuMn multilayers.- List of Contributors.