Complex magnetism and magnetic field-driven electrical polarization in   Co$_3$TeO$_6$
  The magnetic and electrical properties of Co$_3$TeO$_6$ single-crystals with corundum related structure reveal a magnetic-field induced polarization below 21 K. A sharp peak in the specific heat at \approx 18 K indicates a reconstructive-type first-order phase transition. From second-harmonic generation (SHG) measurements breaking of inversion symmetry is evident and the point-group symmetry was determined as m. The temperature and magnetic-field dependence of the magnetic and electrical polarizations are discussed in the light of the SHG results. 
M. Hudl, R. Mathieu, S. A. Ivanov, M. Weil, V. Carolus, Th.   Lottermoser, M. Fiebig, Y. Tokunaga, Y. Taguchi, Y. Tokura and...
cond-mat.str-el cond-mat.mtrl-sci