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arXiv · 1405.1528

Correlation-driven electronic multiferroicity in (TMTTF)$_2$-$X$ organic crystals

G. Giovannetti·R. Nourafkan·G. Kotliar·M. Capone
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Abstract

Using a combination of density functional theory and dynamical mean field theory we show that electric polarization and magnetism are strongly intertwined in (TMTTF)$_2$-$X$ (X$=$PF$_6$, As$F_6$, and SbF$_6$) organic crystals and they originate from short-range Coulomb interactions. Electronic correlations induce a charge-ordered state which, combined with the molecular dimerization, gives rise to a finite electronic polarization and to a ferroelectric state. We predict that the value of the electronic polarization is enhanced by the onset of antiferromagnetism showing a sizable magnetoelectric leading to a multiferroic behavior of (TMTTF)$_2$-$X$ compounds.

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G. Giovannetti, R. Nourafkan, G. Kotliar, M. Capone. 2014-05-07. Correlation-driven electronic multiferroicity in (TMTTF)$_2$-$X$ organic crystals. https://doi.org/10.1103/physrevb.91.125130

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