Influence of severe plastic deformation on superconducting properties of Re and In

• Published in: Physica. C, Superconductivity Vol. 590; p. 1353945
• Main Authors: Idczak, R., Nowak, W., Babij, M., Tran, V.H.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.11.2021; Elsevier BV
• Subjects: Critical field (superconductivity); Crystal defects; Defect annealing; Deformation; Electric resistance; Electrical resistivity; Foils; Indium; Magnetic properties; PALS; Plastic deformation; Plastics; Rhenium; Room temperature; SQUID; Structural defects; Superconductivity; 74.25.-q; Structural defects; SQUID; 74.62.Dh; Superconductivity; 78.70.Bj; PALS
• ISSN: 0921-4534; 1873-2143
• DOI: 10.1016/j.physc.2021.1353945

•Pure Re and In samples were studied by PALS, resistivity and magnetic measurements.•Lattice defects greatly enhance superconducting properties of Re.•Plastic deformation practically does not affect superconducting properties of In. The positron lifetime annihilation spectroscopy, magnetic and electrical resistivity data obtained for the pure polycrystalline rhenium and indium samples were compared with corresponding results obtained for samples after severe plastic deformation (rolling at room temperature). In the case of Re, the results clearly show that the superconducting properties of this material can be greatly enhanced by introducing large number of lattice defects into Re matrix. In particular, the rolled Re sample is type-II superconductor with the critical temperature Tc= 2.6 K and the upper critical field μ0Hc2≤0.034 T. Moreover, the resistivity data reveal that in the highly defected parts of the Re metal, the superconductivity emerges at 3.2–3.3 K and the magnetic field of μ0H=0.09 T is not high enough to fully restore the normal state in those parts of the studied material. In contrast to Re, severe plastic deformation performed at room temperature does noticebly not affect the superconducting properties of the In material. The positron lifetime annihilation spectra reveal that the concentration of the lattice defects in the rolled and the annealed samples is close to each other. We conclude that, the observed changes in superconducting properties of rolled Re (this work) and Ta (earlier work) cannot be caused by introducing additional quantities of impurities during rolling procedure and it must be connected with the presence of lattice defects in the rolled foils.