Magnetic properties and magnetoresistance of the DyMnB4 compound

The magnetic field and temperature dependencies of the magnetization and el ectrical resistance of the DyMnB4, ternary compound have been measured up t p 14 T and within the temperature range 4.2-300 K. The magnetization of DyM nB4 shows a complex behavior due to the presence of two magnetic sublattice s. In zero magnetic field the electrical resistance has a temperature depen dence typical of metals with a. magnetic contribution of 0.38 mu Omega cm K -1 in the temperature range between 4.2 and 22 K. Our data suggest the occu rrence of a transformation from the metallic state to the non-metallic stat e in a magnetic field up to 13 T. As a result the magnetoresistance of DyMn B4 at temperature below -22, K strongly increases with the decreasing of te mperature and at 4.2 K and in a magnetic field of 13 T reaches about 300% o f its zero-field value. (C) 2001 Elsevier Science B.V. All rights reserved.