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arXiv · 0912.0295

Method for reliable realization of a varphi Josephson junction

N. G. Pugach·E. Goldobin·R. Kleiner·D. Koelle
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Abstract

We propose a method to realize a $ϕ$ Josephson junction by combining alternating 0 and $π$ parts (sub junctions) with an intrinsically non-sinusoidal current-phase relation (CPR). Conditions for the realization of the $ϕ$ ground state are analyzed. It is shown that taking into account the non-sinusoidal CPR for a "clean junction with a ferromagnetic (F) barrier, one can significantly enlarge the domain (regime of suitable F-layer thicknesses) of the $ϕ$ ground state and make the practical realization of $ϕ$ Josephson junctions feasible. Such junctions may also have two different stable solutions, such as 0 and $π$, 0 and $ϕ$, or $ϕ$ and $π$.

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N. G. Pugach, E. Goldobin, R. Kleiner, D. Koelle. 2009-12-01. Method for reliable realization of a varphi Josephson junction. https://doi.org/10.1103/physrevb.81.104513

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