Strain effect on thermodynamic properties of superconducting Nb2InC

Abstract

Well-known from their electric and mechanical properties, the MAX phases have proven to be good candidates for replacement of commonly used materials such as steel, copper and tungsten. Together with industrial usefulness, some representatives of this large group manifest the ability of superconducting state occurrence. Above factors complemented with still unexplained coupling mechanism lead to the necessity of extensive investigations on MAX phases on this field. The subject of this research is focused on the thermodynamic properties of superconducting state of Nb2InC. Using the strong-coupling Eliashberg theory of superconductivity the values of the superconducting critical temperature (Tc) have been attained together with the order parameter function (Δ), the thermodynamic critical field (Hc) and the specific heat jump (ΔC) at the transition temperature for the range of tension applied to bulk material. Interesting results of strain strongly affecting the thermodynamic properties of superconducting state can be highlighted. Major enrichment has been obtained for the most extreme strain values with best improvement in case of the compressed system. Moreover, significant changes of critical temperature are noticeable with the constrict strain increment (from −4% to −8%) which results in great development of transition temperature from roughly 0 K to about 35 K, respectively. This leads to conclusion that the applying stress on the material may have significant impact on the thermodynamic properties of the superconducting state. Furthermore, great divergence between the free energy difference, entropy difference and specific heat difference of the extreme strains can be observed. Finally, above values allowed to calculate the BCS theory constants which have been collated.