They use the scotch-taped cleaved pyrolytic graphite carrying the wrinkles that resulted from this cleaving to which they also refer as to line defects. They detected experimental evidence for the global zero-resistance state. The experimental data clearly demonstrated that the array of nearly parallel linear defects that form due to the cleaving of the highly oriented pyrolytic graphite hosts one-dimensional superconductivity.

One-Dimensional room temperature and room pressure superconductivity is what part of the theory and claims proposed for LK99 and sulfurized LK99 and PCPOSOS.

Room temperature superconductivity under normal conditions has been a major challenge of physics and material science since its discovery. Here the global room-temperature superconductivity observed in cleaved highly oriented pyrolytic graphite carrying dense arrays of nearly parallel surface line defects is reported. The multiterminal measurements performed at the ambient pressure in the temperature interval 4.5 K ≤ T ≤ 300 K and at magnetic fields 0 ≤ B ≤ 9 T applied perpendicular to the basal graphitic planes reveal that the superconducting critical current Ic(T, B) is governed by the normal state resistance RN(T, B) so that Ic(T, B) is proportional to 1/RN(T, B). Magnetization M(T, B) measurements of superconducting screening and hysteresis loops together with the critical current oscillations with temperature that are characteristic for superconductor-ferromagnet-superconductor Josephson chains, provide strong support for the occurrence of superconductivity at T over 300 K. A theory of global superconductivity emerging in the array of linear structural defects is developed which well describes the experimental findings and demonstrate that global superconductivity arises as a global phase coherence of superconducting granules in linear defects promoted by the stabilizing effect of underlying Bernal graphite via tunneling coupling to the three dimensional (3D) material.

The mercury-based cuprate HgBa2Ca2Cu3O9 shows the highest Tc = 135 K under the ambient pressure for the accepted uncontroversial best.