High-field-magnetization study of an ErMn6Sn6 single crystal

In previous investigations, it was shown that the compound ErMn6Sn6, that crystallizes in the HfFe6Ge6-type of structure, orders in a helimagnetic state at T-N = 352 K, with the moments rotating within the [001] plane. In the helimagnetic state, metamagnetic behavior is observed, the critical field increasing when the temperature decreases from TN to 220 K and then decreasing with further decrease of the temperature from 200 to 75 K. At this latter temperature, the compound orders ferrimagnetically with the moments in the [001] plane. Very peculiarly, the in-plane magnetocrystalline anisotropy was found to decrease with temperature decreasing from 125 to 4.2 K. The magnetization of ErMn6Sn6 single crystals has been measured in magnetic fields up to 51 T. The measurements were performed at 4.2 K in the ferrimagnetic state and at 125 K in the helimagnetic state with the magnetic field applied along the three principal crystallographic directions. The measured magnetic isotherms are discussed in terms of the competition between the Er-Mn exchange interaction and the magnetocrystalline anisotropies of the Er and the Mn magnetic sublattice. (c) 2005 Elsevier B.V. All rights reserved.