External strain effect on the electronic and mechanical properties of the superconductor Nb2InC

Abstract We use first-principles method to investigate the effects of external strain e on the structural, mechanical and electronic properties for the superconductor Nb 2 InC. The results show that the tensile strain induces an isostructural phase transition in Nb 2 InC. The elastic constants C ij , bulk modulus B , shear modulus G , Young's moduli E , and Poisson ratio v ij of Nb 2 InC were also investigated in the range from e =−10% to e =10%. It indicates that Nb 2 InC is mechanically stable under external strain, and its brittle–ductile transition occurs at e =3.5%. Moreover, Nb 2 InC gets a negative Poisson ratio at e =4%. The calculated electronic structures indicate that the Nb–C bonding is stronger than Nb–In bonding in Nb 2 InC. The energy band structures and densities of states of strained Nb 2 InC were also calculated and discussed in detail. From these calculations, it is clear that the related properties of Nb 2 InC can be easily tuned by strain. Therefore, our findings are very useful to tailor the physical properties of Nb 2 InC by using strain engineering.