Resistivity, Hall effect, and anisotropic superconducting coherence lengths of HgBa₂CaCu₂O₆ thin films with different morphology

Author(s)

Herbert Richter, Wolfgang Lang, Martin Peruzzi, Helmut Hattmannsdorfer, John Hay Durrell, Johannes David Pedarnig

Abstract

Thin films of the high-temperature superconductor HgBa₂CaCu₂O₆ have been prepared on SrTiO₃ substrates by pulsed-laser deposition of precursor films and subsequent annealing in mercury-vapor atmosphere. The microstructural properties of such films can vary considerably and have been analyzed by x-ray analysis and atomic force microscopy. Whereas the resistivity is significantly enhanced in samples with coarse-grained structure, the Hall effect shows little
variation. This disparity is discussed based on models for transport properties in granular materials. We find that, despite of the morphological variation, all samples have similar superconducting properties. The critical temperatures Tc ∼ 121.2 K …122.0 K, resistivity, and Hall data indicate that the samples are optimally doped. The analyses of superconducting order parameter fluctuations in zero and finite magnetic fields yield the in-plane ξ_ab(0) ∼ 2.3 nm …2.8 nm and out-of-plane ξ_c(0) ∼ 0.17 nm …0.24 nm Ginzburg–Landau coherence lengths at zero temperature. Hall measurements provide estimates of carrier scattering defects in the normal state and vortex pinning properties in the superconducting state inside the grains.

Organisation(s)

Electronic Properties of Materials

External organisation(s)

Johannes Kepler Universität Linz, University of Cambridge, Universität Wien

Journal

Superconductor Science & Technology

Volume

34

No. of pages

8

ISSN

0953-2048

DOI

https://doi.org/10.1088/1361-6668/abdedf

Publication date

02-2021

Peer reviewed

Yes

Austrian Fields of Science 2012

103033 Superconductivity

Keywords

ASJC Scopus subject areas

Condensed Matter Physics, Ceramics and Composites, Metals and Alloys, Materials Chemistry, Electrical and Electronic Engineering

Portal url

https://ucris.univie.ac.at/portal/en/publications/resistivity-hall-effect-and-anisotropic-superconducting-coherence-lengths-of-hgba2cacu2o6-thin-films-with-different-morphology(6e90f71d-5872-4947-b09a-a9ffeb739fc3).html