Pseudo spin-valve switch based on ferromagnet/superconductor/ferromagnet trilayer microbridge

L. N. Karelina; V. V. Bol'ginov; Sh. A. Erkenov; S. V. Egorov; I. A. Golovchanskiy; V. I. Chichkov; A. ben Hamida; V. V. Ryazanov

arXiv · 2009.00498

Pseudo spin-valve switch based on ferromagnet/superconductor/ferromagnet trilayer microbridge

L. N. Karelina·V. V. Bol'ginov·Sh. A. Erkenov·S. V. Egorov·I. A. Golovchanskiy·V. I. Chichkov·A. ben Hamida·V. V. Ryazanov

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Abstract

A noticeable magnetoresistive effect has been observed on ferromagnet/superconductor/ferromagnet (FSF) microbridges based on diluted ferromagnetic PdFe alloy containing as small as 1% magnetic atoms. Microstructuring of the FSF trilayers does not destroy the effect: the most pronounced curves were obtained on the smallest bridges of 6-8 um wide and 10-15 um long. Below the superconducting transition we are able to control the critical current of microbridges by switching between P and AP orientations of magnetizations of PdFe layers. The operation of FSF-bridge as a magnetic switch is demonstrated in several regimes providing significant voltage discrimination between digital states or remarkably low bit error rate.

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L. N. Karelina, V. V. Bol'ginov, Sh. A. Erkenov, S. V. Egorov, I. A. Golovchanskiy, V. I. Chichkov, A. ben Hamida, V. V. Ryazanov. 2020-09-01. Pseudo spin-valve switch based on ferromagnet/superconductor/ferromagnet trilayer microbridge. https://arxiv.org/abs/2009.00498

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