Evidence for room temperature superconductivity at graphite interfaces
arXiv:1709.00259 · doi:10.1007/s40509-017-0131-0
Abstract
In the last 43 years several hints were reported suggesting the existence of granular superconductivity above room temperature in different graphite-based systems. In this paper some of the results are reviewed, giving special attention to those obtained in water and n-heptane treated graphite powders, commercial and natural bulk graphite samples with different characteristics as well as transmission electron microscope (TEM) lamellae. The overall results indicate that superconducting regions exist and are localized at certain internal interfaces of the graphite structure. The existence of the rhombohedral graphite phase in all samples with superconducting-like properties suggests its interfaces with the Bernal phase as a possible origin for the high-temperature superconductivity, as theoretical calculations predict. High precision electrical resistance and magnetization measurements were used to identify a transition at K. To check for the existence of true zero resistance paths in the samples we used local magnetic measurements, which results support the existence of superconducting regions at such high temperatures.
10 pages, 9 figures, 2nd International Workshop "Towards Room Temperature Superconductivity: Superhydrides and more", Orange California May 2017. To be published in "Quantum Studies: Mathematics and Foundations" (Springer Nature)
References in corpus (7)
- Bipolar supercurrent in graphene
- Evidence of Josephson-coupled superconducting regions at the interfaces of Highly Oriented Pyrolytic Graphite
- Identification of a possible superconducting transition above room temperature in natural graphite crystals
- Intrinsic Superconductivity at 25 K in Highly Oriented Pyrolytic Graphite
- Flat Bands near Fermi Level of Topological Line Defects on Graphite
- Granular superconductivity below 5~K in SPI-II pyrolytic graphite
- Local magnetic measurements of permanent current paths in a natural graphite crystal