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arXiv · 1608.03490

Interplay between conducting and magnetic systems in the antiferromagnetic organic superconductor $\kappa$-(BETS)$_2$FeBr$_4$

Mark. V. Kartsovnik·Michael Kunz·Ludwig Schaidhammer·Florian Kollmannsberger·Werner Biberacher·Natalia D. Kushch·Akira Miyazaki·Hideki Fujiwara
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Abstract

The mutual influence of the conduction electron system provided by organic donor layers and magnetic system localized in insulating layers of the molecular charge transfer salt $\kappa$-(BETS)$_2$FeBr$_4$ has been studied. It is demonstrated that besides the high-field re-entrant superconducting state, the interaction between the two systems plays important role for the low-field superconductivity. The coupling of normal-state charge carriers to the magnetic system is reflected in magnetic quantum oscillations and can be evaluated based on the angle-dependent beating behaviour of the oscillations. On the other hand, the conduction electrons have their impact on the magnetic system, which is revealed through the pressure-induced changes of the magnetic phase diagram of the material.

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Mark. V. Kartsovnik, Michael Kunz, Ludwig Schaidhammer, Florian Kollmannsberger, Werner Biberacher, Natalia D. Kushch, Akira Miyazaki, Hideki Fujiwara. 2016-08-11. Interplay between conducting and magnetic systems in the antiferromagnetic organic superconductor $\kappa$-(BETS)$_2$FeBr$_4$. https://doi.org/10.1007/s10948-016-3829-z

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