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From spin-Peierls to superconductivity: (TMTTF)_2PF_6 under high pressure

D. Jaccard·H. Wilhelm·D. Jerome·J. Moser·C. Carcel·J. M. Fabre
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Abstract

The nature of the attractive electron-electron interaction, leading to the formation of Cooper-pairs in unconventional superconductors has still to be fully understood and is subject to intensive research. Here we show that the sequence spin-Peierls, antiferromagnetism, superconductivity observed in (TMTTF)_2PF_6 under pressure makes the (TM)_2X phase diagram universal. We argue that the suppression of the spin-Peierls transition under pressure, the close vicinity of antiferromagnetic and superconducting phases at high pressure as well as the existence of critical antiferromagnetic fluctuations above T_c strongly support the intriguing possibility that the interchain exchange of antiferromagnetic fluctuations provides the pairing mechanism required for bound charge carriers.

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D. Jaccard, H. Wilhelm, D. Jerome, J. Moser, C. Carcel, J. M. Fabre. 2000-05-23. From spin-Peierls to superconductivity: (TMTTF)_2PF_6 under high pressure. https://doi.org/10.1088/0953-8984%2F13%2F4%2F104

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