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Correlation Between the Superconducting and Normal State Properties of Amorphous Molybdenum-Silicon Alloys

  • A. S. Edelstein
  • S. R. Ovshinsky
  • H. Sadate-Akhavi
  • J. Wood
Part of the Institute for Amorphous Studies Series book series (IASS)

Abstract

We have made a study of the resistivity, ρ(T), and the structural and superconducting properties of amorphous Mol-xSix Besides the usual interest in studying a metal to nonmetal transition, this system has the additional feature that Si changes from acting metallic for x << 1 to acting nonmetallic for x ~ 1. Murarka et al. (1) measured the resistivity of both amorphous and crystallized cosputtered films of MoSi and a comparison of their data with ours will be made below. We have observed a large increase in dρ(297)/dx with increasing x at x = x0 ≡ 0.63 ± 0.05 which is most likely associated with an electronic transition involving the Si valence electrons. A tentative model for this transition is presented below. Besides observing this increase in d ρ(297)/dx, the specific results pertinent to superconductivity are:
  1. 1.

    The initial linear decrease of the superconducting transition temperature T­c is 0.075 K/at.% Si. This is consistent with the e/a dependence found by Collver and Hammond (2) for near neighbor amorphous 4d metals if one assumes that each Si atom contributes 4 electrons to the conduction band.

     
  2. 2.

    Supperconductivity persists up to at least 64 at.% i.e., slightly into the concentration region where the resistivity begins to increase. As x→xo ­from below, the superconducting transition width ΔT­c increases rapidly until at x ≃ xo the width ΔTc becomes comparable to Rc.

     
  3. 3.

    For x > xo, Tc, if it exists, is less than 1.5K.

     

Keywords

Percolation Theory Superconducting Transition Temperature Room Temperature Resistivity Tentative Model Transmission Electron Diffraction 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Plenum Press, New York 1991

Authors and Affiliations

  • A. S. Edelstein
    • 1
  • S. R. Ovshinsky
    • 1
  • H. Sadate-Akhavi
    • 1
  • J. Wood
    • 1
  1. 1.Energy Conversion Devices, Inc.TroyUSA

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