Magnetodielectric and magnetoelastic coupling in Co4Nb2O9 below Neel temperature

The dielectric constant of Co4Nb2O9 shows an obvious upturn below Neel temperature (T-N), and the magnetic field enhances this anomaly. Thus the magnetodielectric effect exists in the entire temperature region below T-N, not only near T-N as reported previously. At the same time, the strain exhibits a drop below T-N, and the magnetic field suppresses this anomaly, demonstrating magnetoelastic coupling in Co4Nb2O9. The origin of dielectric anomaly and magnetodielectric effect below T-N may be related to the phonon mode shifts induced by magnetoelastic coupling. (C) 2016 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).