Multiferroic properties of o-LuMnO$_3$ controlled by b-axis strain
  Strain is a leading candidate for controlling magnetoelectric coupling in multiferroics. Here, we use x-ray diffraction to study the coupling between magnetic order and structural distortion in epitaxial films of the orthorhombic (o-) perovskite LuMnO$_3$. An antiferromagnetic spin canting in the E-type magnetic structure is shown to be related to the ferroelectrically induced structural distortion and to a change in the magnetic propagation vector. By comparing films of different orientations and thicknesses, these quantities are found to be controlled by b-axis strain. It is shown that compressive strain destabilizes the commensurate E-type structure and reduces its accompanying ferroelectric distortion. 
Y. W. Windsor, S. W. Huang, Y. Hu, L. Rettig, A. Alberca, K.   Shimamoto, V.Scagnoli, T. Lippert, C. W. Schneider and U. Staub
cond-mat.str-el