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Competing phases in the high field phase diagram of (TMTSF)$_2$ClO$_4$

S. Haddad·S. Charfi-Kaddour·C. Nickel·M. Héritier·R. Bennaceur
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Abstract

A model is presented for the high field phase diagram of (TMTSF)$_2$ClO$_4$, taking into account the anion ordering, which splits the Fermi surface in two bands. For strong enough field, the largest metal-SDW critical temperature corresponds to the N=0 phase, which originates from two intraband nesting processes. At lower temperature, the competition between these processes puts at disadvantage the N=0 phase vs. the N=1 phase, which is due to interband nesting. A first order transition takes then place from the N=0 to N=1 phase. We ascribe to this effect the experimentally observed phase diagrams.

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S. Haddad, S. Charfi-Kaddour, C. Nickel, M. Héritier, R. Bennaceur. 2002-07-01. Competing phases in the high field phase diagram of (TMTSF)$_2$ClO$_4$. https://doi.org/10.1103/physrevlett.89.087001

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