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Evidence for Suppression of Superconductivity by Spin Imbalance in Co-Al-Co single electron transistors

C. D. Chen·Watson Kuo·D. S. Chung·J. H. Shyu·C. S. Wu
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Abstract

Spin imbalance is predicted to lead to suppression of superconductivity. We report phenomena manifesting this effect under spin-polarized quasiparticle currents in ferromagnet-superconductor-ferromagnet single electron transistors. The measured superconducting gap as a function of magnetic field reveals a dramatic decrease when the magnetizations of the two leads are in opposite orientations. The effect of suppression increases with increas-ing voltage but decreases at elevated temperatures. The possible explanations for these dependences are given. This method may render it applicable to control superconductivity at low temperatures and low fields.

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C. D. Chen, Watson Kuo, D. S. Chung, J. H. Shyu, C. S. Wu. 2001-03-31. Evidence for Suppression of Superconductivity by Spin Imbalance in Co-Al-Co single electron transistors. https://doi.org/10.1103/physrevlett.88.047004

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