High-Pressure Effects on the Intermetallic Superconductor Ti_0.85Pd_0.15

Abstract

This work reports superconductivity studies in the intermetallic Ti_0.85Pd_0.15 performed in normal conditions and under hydrostatic pressure. The crystal structure of the compound has a body-centered cubic at room temperature and atmospheric pressure as unstable β-Ti phase. X-ray diffraction pattern shows space group I$m\bar {3}m$ with parameter a = 3.2226(4) Å and density around 5.6242 g/cm³. The superconducting transition temperature, T_C = 3.7 K was determined from resistance, magnetization, and specific heat measurements. The two critical magnetic fields, the coherence length, Ginzburg–Landau parameter, London penetration depth, the superconducting energy gap, the Debye temperature, the electron-phonon coupling constant and density of states at the Fermi level were calculated. These parameters were obtained at ambient pressure. Under hydrostatic pressure, the magnetic susceptibility measurements show a small increment on T_C, the maximum T_C = 3.83 K was obtained at the maximum applied pressure of 1.03 GPa. The slope calculated for T_C as a linear function of pressure was about 0.14 K/GPa, possibly associated with an increase in the electronic density of states.