engleski

Anisotropy and Dimensional Nature of Superconductivity in HgBa2CuO4+δ

Information about the anisotropy of the high-Tc cuprate systems reveals the dimensional properties of the order parameter, i.e. the nature of the superconducting (SC) state. Microwave absorption measurements have proved to be a useful tool for the determination of upper critical fields in high-Tc superconductors, even beyond the experimentally reachable dc magnetic fields. Also, from the phase sensitive complex frequency shift one can extract the ab- and c-axis complex conductivity, which is particularly sensitive if the proper sample geometry is chosen. Here we present the measurements of a high quality single crystal of HgBa2CuO4+δ, which can be considered as the model single-layered high-Tc superconductor, known for its unique property to confine extrinsic disorder away from the superconducting layer, and the determined upper critical fields in two orientations (Bdc || c-axis and Bdc || ab-plane). From the analisys of the in-plane and out-of-plane complex conductivity we determine the onset of the superconducting fluctuations and bring new results regarding the dimensionality of the SC state in the cuprates.

superconductivity; cuprates; microwaves; anisotropy

nije evidentirano