The effect of martensitic phase transition from cubic to tetragonal on the physical properties of V3Si superconductor


Tutuncu H. M., Uzunok H. Y., Srivastava G. P., ÖZDEMİR V., UĞUR G.

INTERMETALLICS, vol.96, pp.25-32, 2018 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 96
  • Publication Date: 2018
  • Doi Number: 10.1016/j.intermet.2018.02.010
  • Journal Name: INTERMETALLICS
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.25-32
  • Keywords: Intermetallics, Density functional theory, electronic structure, Superconducting properties, Ab-initio calculations, Physical properties, EG OPTICAL PHONON, RAMAN-SCATTERING, ELECTRONIC-STRUCTURE, HEAT-CAPACITY, TUNNELING ALPHA-2F(OMEGA), BAND-STRUCTURE, FERMI-SURFACE, X-RAY, NB3SN, TEMPERATURE
  • Gazi University Affiliated: Yes

Abstract

We report results of ab-initio studies for the structural, electronic, lattice dynamical and electron-phonon interaction properties of cubic and tetragonal phases of V3Si by using the plane-wave pseudopotential method, the density-functional theory, and a linear-response technique. Our total energy results propose that the martensitic transition from cubic to a tetragonal variant of the A15 structure takes place with a very little change in the unit cell volume and total energy. Thus, the electronic and lattice dynamical properties of both phases look like similar to each other. Our electron-phonon interaction calculations reveal that the phonon properties of V lattice considerably enter into electron-phonon interaction calculations due to noteworthy presence of transition metal d electrons at the Fermi level. Using the calculated value of 1.15 for the average electron-phonon coupling parameter of both phases, the superconducting critical temperature and the electronic specific heat coefficient are evaluated to be 17.3 K and 54.5 mJ/(molK(2)), respectively, in gratifying agreement with their measured values of 17 K and 53 mJ/(molK(2)).