Half - h/2e - Oscillations of SQUIDs

C. W. Schneider; G. Hammerl; G. Logvenov; T. Kopp; J. R. Kirtley; P. J. Hirschfeld; J. Mannhart

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Half - h/2e - Oscillations of SQUIDs

C. W. Schneider·G. Hammerl·G. Logvenov·T. Kopp·J. R. Kirtley·P. J. Hirschfeld·J. Mannhart

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Abstract

The current-voltage characteristics of Superconducting Quantum Interference Devices (SQUIDs) are known to modulate as a function of applied magnetic field with a period of one flux quantum $Φ_0=h$/2e. Here we report on the fabrication and properties of SQUIDs modulating with a period of $1/2\timesΦ_0$. The characteristics of these bicrystal SQUIDs are consistent with either a strong sin(2$ϕ$) component of the current-phase relation of the Josephson current, or with an interaction between the Cooper-pairs, causing an admixture of quartets to the condensate.

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C. W. Schneider, G. Hammerl, G. Logvenov, T. Kopp, J. R. Kirtley, P. J. Hirschfeld, J. Mannhart. 2004-03-23. Half - h/2e - Oscillations of SQUIDs. https://arxiv.org/abs/cond-mat/0403595

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