Low-temperature phenomena in highly doped grained diamond

The contribution deals with low-temperature phenomena observed in highly boron-doped nanocrystalline diamond films grown by plasma enhanced chemical vapour deposition technique. We put special emphasis on the effects likely related to the granular structure of this material. It has been shown that the experimental data concerning critical currents, supercurrents induced by thermal noise in the normal phase and current-induced Josephson's noise in the superconductivity transition region may be consistently explained by a model of superconducting grains interconnected by a single or a few weak links having a characteristic dimension in the nanometer range.