Evidence for multiferroicity in TTF-CA organic molecular crystals
Materials Science
2015-05-14 v1
Abstract
We show by means of ab-initio calculations that the organic molecular crystal TTF-CA is multiferroic: it has an instability to develop spontaneously both ferroelectric and magnetic ordering. Ferroelectricity is driven by a Peierls transition of the TTF-CA in its ionic state. Subsequent antiferromagnetic ordering strongly enhances the opposing electronic contribution to the polarization: it is so large that it switches the direction of the total ferroelectric moment. Within an extended Hubbard model we capture the essence of the electronic interactions in TTF-CA, confirm the presence of a multiferroic groundstate and clarify how this state develops microscopically.
Keywords
Cite
@article{arxiv.0908.3264,
title = {Evidence for multiferroicity in TTF-CA organic molecular crystals},
author = {Gianluca Giovannetti and Sanjeev Kumar and Alessandro Stroppa and Jeroen van den Brink and Silvia Picozzi},
journal= {arXiv preprint arXiv:0908.3264},
year = {2015}
}
Comments
4 pages, 4 figures