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Superconductivity in an organic insulator at very high magnetic fields

L. Balicas·J. S. Brooks·K. Storr·S. Uji·M. Tokumoto·H. Tanaka·H. Kobayashi·A. Kobayashi·V. Barzykin·L. P. Gor'kov
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Abstract

We investigate by electrical transport the field-induced superconducting state (FISC) in the organic conductor $λ$-(BETS)$_2$FeCl$_4$. Below 4 K, antiferromagnetic-insulator, metallic, and eventually superconducting (FISC) ground states are observed with increasing in-plane magnetic field. The FISC state survives between 18 and 41 T, and can be interpreted in terms of the Jaccarino-Peter effect, where the external magnetic field {\em compensates} the exchange field of aligned Fe$^{3+}$ ions. We further argue that the Fe$^{3+}$ moments are essential to stabilize the resulting singlet, two-dimensional superconducting state

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L. Balicas, J. S. Brooks, K. Storr, S. Uji, M. Tokumoto, H. Tanaka, H. Kobayashi, A. Kobayashi, V. Barzykin, L. P. Gor'kov. 2001-03-22. Superconductivity in an organic insulator at very high magnetic fields. https://doi.org/10.1103/physrevlett.87.067002

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