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Gate-induced band ferromagnetism in an organic polymer

Ryotaro Arita·Yuji Suwa·Kazuhiko Kuroki·Hideo Aoki
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Abstract

We propose that a chain of five-membered rings (polyaminotriazole) should be ferromagnetic with an appropriate doping that is envisaged to be feasible with an FET structure. The ferromagnetism is confirmed by a spin density functional calculation, which also shows that ferromagnetism survives the Peierls instability. We explain the magnetism in terms of Mielke and Tasaki's flat-band ferromagnetism with the Hubbard model. This opens a new possibility of band ferromagnetism in purely organic polymers.

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Ryotaro Arita, Yuji Suwa, Kazuhiko Kuroki, Hideo Aoki. 2001-08-27. Gate-induced band ferromagnetism in an organic polymer. https://doi.org/10.1103/physrevlett.88.127202

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