Comparison of superconducting parameters of A 15- and σ-phases of Nb−Pt
- 28 Downloads
The superconducting properties of A 15- and σ-phases of the system Nb−Pt were investigated. Alloys of compositions Nb3Pt, Nb2Pt, and Nb62Pt38 were prepared by arc melting and subjected to optical microscopic and x-ray analysis for structure determination. The transition temperatures were measured inductively as well as resistively. The temperature dependences of critical fields were measured up to 35 kG. The A 15-phase has aT c value of 8.97K and a zero temperature upper critical fieldH c2(0) of 100 kG as compared to aT c value of 2.14K and anH c2(0) value of 14kG for the σ-phase. A comparison with theoretical upper critical field values seems to indicate that a spin-orbit coupling mechanism is responsible for the higher value ofH c2(0) in the case of the A 15-phase alloy. The temperature dependent resistance up to 300 K is also measured and discussed for both the phases.
Unable to display preview. Download preview PDF.
- 3.H.R. Khan, K. Lüders, Ch.J. Raub, Z. Szücs: Phys. stat. sol. (b)78, K107 (1976)Google Scholar
- 5.P. Greenfield, P.A. Beck: Trans. Am. Inst. Min. (Metall) Eng.206, 265 (1956)Google Scholar
- 6.R.M.Waterstrat, R.C.Manuszewski: NBS IR 73-415, August 1975Google Scholar
- 16.K. Maki: Physics1, 21; 127 (1964)Google Scholar
- 17.G.H. Bongi, R. Flükiger, A. Treyvaud, Ø. Fischer: J. Low Temp. Phys.23, 543; 571 (1976)Google Scholar
- 18.A.H.Wilson:The theory of metals, 2nd ed. (Cambridge University Press 1956)Google Scholar
- 20.H.R.Khan, K.Lüders, Ch.J.Raub, Z.Szücs: To be published in phys. stat. sol.84bGoogle Scholar