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hc/4e oscillations in a model for (100)/(110) SQUIDs of d-wave superconductors

L. M. Leon Hilario·A. A. Aligia
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Abstract

We use a model of hard-core bosons to describe a SQUID built with two crystals of $d_{x^2-y^2}$-superconductors with orientations (100) and (110). Across the two faceted (100)/(110) interfaces, the structure of the superconducting order parameter leads to an alternating sign of the local Josephson coupling, and the possibility of quartet formation. Using a mapping of the boson model to an $XXZ$ model, we calculate numerically the energy of the system as a function of the applied magnetic flux, finding signals of $hc/4e$ oscillations in a certain region of parameters. This region has a large overlap to that at which binding of bosons exists.

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L. M. Leon Hilario, A. A. Aligia. 2007-02-06. hc/4e oscillations in a model for (100)/(110) SQUIDs of d-wave superconductors. https://doi.org/10.1016/j.physc.2005.12.058

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