\(\hbox {Nb}_{{2}}\) SC and \(\hbox {Nb}_{{2}}\) AsC are among the identified superconducting MAX phases, both exhibiting a transition temperature \(\hbox {T}_{{c}}\) lower than 10 K. These compounds appear to belong to the conventional class of superconductors. By calculating the electron-phonon couplings of these materials, we have found that the predicted transition temperatures are approximately 6 K for \(\hbox {Nb}_{{2}}\) SC and 2 K for \(\hbox {Nb}_{{2}}\) AsC, closely matching the experimental findings. However, when subjected to pressure or strain, \(\hbox {Nb}_{{2}}\) SC and \(\hbox {Nb}_{{2}}\) AsC exhibit contrasting behaviors. While the transition temperature of \(\hbox {Nb}_{{2}}\) SC can be doubled by applying pressure up to 50 GPa, the transition temperature of \(\hbox {Nb}_{{2}}\) AsC significantly decreases under the same pressure. On the other hand, in the case of \(\hbox {Nb}_{{2}}\) AsC, a uniaxial tensile strain of approximately 2% along the c direction can enhance the compound’s transition temperature by about 40%. These results show that with the right pressure or strain, it is possible to increase superconducting transition temperature in the \(\hbox {Nb}_{{2}}\) AC compounds.
