Intrinsic Superconductivity at 25 K in Highly Oriented Pyrolytic Graphite

Abstract

High resolution magnetoresistance data in highly oriented pyrolytic graphite thin samples manifest non-homogenous superconductivity with critical temperature $T_c\sim 25$K. These data exhibit: i) hysteretic loops of resistance versus magnetic field similar to Josephson-coupled grains, ii) quantum Andreev's resonances and iii) absence of the Schubnikov-de Haas oscillations. The results indicate that graphite is a system with non-percolative superconducting domains immersed in a semiconducting-like matrix. As possible origin of the superconductivity in graphite we discuss interior-gap superconductivity when two very different electronic masses are present.

5 pages, 3 figures

References in corpus (9)

• First direct observation of Dirac fermions in graphite
• Phase analysis of quantum oscillations in graphite
• Metal-Insulator-Like Behavior in Semimetallic Bismuth and Graphite
• Experimental Evidence for Two-Dimensional Magnetic Order in Proton Bombarded Graphite
• Low energy excitations in graphite: The role of dimensionality and lattice defects
• Electrostatic Force Microscopy on Oriented Graphite Surfaces: Where Insulating and Conducting Behaviors Coexist
• Fermion Cooper Pairing with Unequal Masses: Standard Field Theory Approach
• Bose-Einstein condensation of strongly correlated electrons and phonons in cuprate superconductors
• Fluctuation spectroscopy of granularity in superconducting structures

Cited by in corpus (2)

• Quantum Andreev Oscillations in normal-superconducting-normal nanostructures
• From Ohmic to Ballistic Transport in Oriented Graphite