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Evidence of Collective Charge Behavior in the Insulating State of Ultrathin Films of Superconducting Metals

C. Christiansen·L. M. Hernandez·A. M. Goldman
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Abstract

Nonlinear I-V characteristics have been observed in insulating quench-condensed films which are locally superconducting. We suggest an interpretation in terms of the enhancement of conduction by the depinning of a Cooper pair charge density wave, Cooper pair crystal, or Cooper pair glass that may characterize the insulating regime of locally superconducting films. We propose that this is a more likely description than the Coulomb blockade or charge-anticharge unbinding phenomena.

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C. Christiansen, L. M. Hernandez, A. M. Goldman. 2001-08-20. Evidence of Collective Charge Behavior in the Insulating State of Ultrathin Films of Superconducting Metals. https://doi.org/10.1103/physrevlett.88.037004

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