Weak ferromagnetism and magnetoelectric coupling in bismuth ferrite

Claude Ederer∗ and Nicola A. Spaldin 

Materials Research Laboratory and Materials Department, University of California, Santa Barbara, CA 93106, U.S.A. 

(Dated: February 2, 2008)

Abstract

We analyze the coupling between the ferroelectric and magnetic order parameters in the magnetodensity approximation and the LSDA+U method. We show that weak ferromagnetism of the Dzyaloshinskii-Moriya type occurs in this material, and we analyze the coupling between the resulting magnetization and

the structural distortions. We explore the possibility of electric-field-induced magnetization reversal and show that, although it is unlikely to be realized in BiFeO3, it is not in general impossible.

Finally we outline the conditions that must be fulfilled to achieve switching of the magnetization using an electric field.

To download the article click on the link below:

http://arxiv.org/pdf/cond-mat/0407003.pdf