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arXiv · 1702.08828

Superconducting spin valves controlled by spiral re-orientation in B20-family magnets

N. G. Pugach·M. Safonchik·T. Champel·M. E. Zhitomirsky·E. Lähderanta·M. Eschrig·C. Lacroix
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Abstract

We propose a superconducting spin-triplet valve, which consists of a superconductor and an itinerant magnetic material, with the magnet showing an intrinsic non-collinear order characterized by a wave vector that may be aligned in a few equivalent preferred directions under control of a weak external magnetic field. Re-orienting the spiral direction allows one to controllably modify long-range spin-triplet superconducting correlations, leading to spin-valve switching behavior. Our results indicate that the spin-valve effect may be noticeable. This bilayer may be used as a magnetic memory element for cryogenic nanoelectronics. It has the following advantages in comparison to superconducting spin valves proposed previously: (i) it contains only one magnetic layer, which may be more easily fabricated and controlled, (ii) its ground states are separated by a potential barrier, which solves the "half-select" problem of the addressed switch of memory elements.

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N. G. Pugach, M. Safonchik, T. Champel, M. E. Zhitomirsky, E. Lähderanta, M. Eschrig, C. Lacroix. 2017-02-28. Superconducting spin valves controlled by spiral re-orientation in B20-family magnets. https://doi.org/10.1063/1.5000315

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