Strong ferromagnetic-dielectric coupling in multiferroic Lu2CoMnO6   single crystals
  We have grown single crystals of multiferroic double-perovskite Lu2CoMnO6 and studied the directional dependence of their magnetic and dielectric properties. The ferromagnetic order emerges below TC ~ 48K along the crystallographic c axis. Dielectric anomaly arises along the b axis at TC, contrary to the polycrystalline work suggesting ferroelectricity along the c axis. Through the strongly coupled ferromagnetic and dielectric states, the highly non-linear variation of both dielectric constant and magnetization was achieved in application of magnetic fields. This concurrent tunability provides an efficient route to manipulation of multiple order parameters in multiferroics. 
N. Lee, H. Y. Choi, Y. J. Jo, M. S. Seo, S. Y. Park, and Y. J. Choi
cond-mat.str-el