Date of this Version
New Journal of Physics
There has been tremendous research activity in the field of magneto-electric (ME) multiferroics after Kimura et al (2003 Nature 426 55) showed that antiferromagnetic and ferroelectric orders coexist in orthorhombically distorted perovskite TbMnO3 and are strongly coupled. It is now generally accepted that ferroelectricity in TbMnO3 is induced by magnetic long-range order that breaks the symmetry of the crystal and creates a polar axis (Kenzelmann et al 2005 Phys. Rev. Lett. 95 087206). One remaining key question is whether magnetic order can induce ferroelectric polarization that is as large as that of technologically useful materials. We show that ferroelectricity in orthorhombic (o) TmMnO3 is induced by collinear magnetic order, and that the lower limit for its electric polarization is larger than in previously investigated orthorhombic heavy rare-earth manganites. The temperature dependence of the lattice constants provides further evidence of large spin–lattice coupling effects. Our experiments suggest that the ferroelectric polarization in the orthorhombic perovskites with commensurate magnetic ground states could pass the 1 μC cm-2 threshold, as predicted by theory (Sergienko et al 2006 Phys. Rev. Lett. 97 227204; Picozzi et al 2007 Phys. Rev. Lett. 99 227201).
This is an author-created, un-copyedited version of an article accepted for publication in New Journal of Physics. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The definitive publisher authenticated version is available online at dx.doi.org/10.1088/1367-2630/11/4/043019.
Pomjakushin, V. Y., Kenzelmann, M., Dönni, A., Harris, A., Nakajima, T., Mitsuda, S., Tachibana, M., Keller, L., Mesot, J., Kitazawa, H., & Takayama-Muromachi, E. (2009). Evidence for Large Electric Polarization From Collinear Magnetism in TmMnO3. New Journal of Physics, 11 1-9. http://dx.doi.org/10.1088/1367-2630/11/4/043019
Date Posted: 20 August 2015
This document has been peer reviewed.