Electric field induced magnetism decline in organic ferromagnets

Abstract

With an Anderson-like model including electron-electron interaction and electron-lattice interaction, the effect of external electric field on the electric and magnetic properties of quasi-one-dimensional organic ferromagnets is investigated theoretically. The results demonstrate a field-induced magnetism decline of the organic ferromagnet, which manifests a continuous decrease of the total molecular spin and suppression of the spin density wave after a critical field. The analysis of energy band evolution under the field indicates that the field-induced energy levels crossover of the spin-split flat bands is responsible for the magnetism decline. A companied charge polarization and charge transfer between spin radicals and main chain in the OF are observed. Different strength of the internal interactions including electron-electron interaction, hopping integral between radicals and main chain, and electron-lattice interaction is discussed. This work is helpful to understand the property of organic ferromagnets under external field in the situation of organic-ferromagnetic devices.