Superconductivity in highly doped diamond: Role of group III and V impurities

Abstract

This study comprises an investigation of the superconductivity in highly doped diamond, comprising elements from groups III and V acting as acceptor and donor impurities, respectively, within the virtual crystal approximation. Calculations of the electron–phonon coupling were carried out for each case, enlightening the different aspects arising from different doping elements and their consequent impact on the superconducting critical temperature. These calculations indicated that among the hole-doped cases the electron–phonon coupling is strongly related to the optical phonons of the lattice. Regarding the electron-doped systems, it was observed that the coupling had contributions from both optical and acoustic vibrations, leading to high estimates for the critical temperature. Through the comparison between these opposing scenarios, several distinctions between the electron- and hole-doped cases became evident, implying that the mechanisms of superconductivity in doped diamond relate directly to the nature of the impurity added to the system. These results provide further evidence that the electronic and dynamic changes arising from the electron doping of a diamond may lead to superconductivity in high temperatures.