Selected Publications

Superconducting Sweet-Spot in Microcrystalline Graphite Revealed by Point-Contact Spectroscopy

F. Arnold, J. Nyéki, J. Saunders

In this letter, we describe the observation of a magnetic field dependent electronic gap, suggestive of local superconductivity, in the point-contact spectrum of microcrystalline graphite. Magnetic field dependent point-contact spectroscopy has been carried out at a temperature of 1.8 K using an etched aluminum tip. At zero field, a gap structure in the differential conductance is observed, showing a gap of meV. On applying magnetic fields of up to 500 mT, this gap gradually closes, following the theoretical prediction by Ginzburg and Landau for a fully flux-penetrated superconductor. By applying BCS-theory, we infer a critical superconducting temperature of 14K.

Jetp Lett. 107, 577-578 (2018)

doi: 10.1134/S0021364018090023