Unusual magnetic and structural transformations of DyFe4Ge2

J. Liu, D. Paudyal, Y. Mudryk, J. D. Zou, K. A. Gschneidner, Jr., V. K. Pecharsky
2013 Physical Review B  
Magnetization of DyFe 4 Ge 2 measured as function of temperature in 1kOe magnetic field indicates antiferromagnetic (AFM) ordering at T N =62 K followed by two spin reorientation transitions at T f1 =52 K and T f2 =32 K and one unusual anomaly at 15 K (T f3 ). Three transitions (T f1 , T f2 , and T N ) are further confirmed by heat-capacity measurement in a zero magnetic field. The two low temperature magnetic transitions are broadened and gradually vanish when the applied magnetic field
more » ... gnetic field exceeds 30 kOe, and the AFM transition shifts toward low temperature with increasing magnetic field. Reentrant magnetic glassy state is observed below freezing point T f3 = 15 K. Two field-induced metamagnetic phase transitions are observed between 2 and 50 K in fields below 140 kOe. The temperature-magnetic field phase diagram has been constructed. The first principles electronic structure calculations show that the paramagnetic tetragonal structure of DyFe 4 Ge 2 is stable at high temperature. The calculations with collinear Dy spins confirm ferrimagnetic orthorhombic DyFe 4 Ge 2 as the ground state structure, which is experimentally a stable structure with applied magnetic field. PACS Nos: 61.50.Ks, 71.20.Eh, 71.15.Mb Rare earth-based intermetallic compounds continue to draw considerable attention due to their importance in understanding of fundamental structure-property relationships, and potential for practical applications based on a variety of phenomena, including strong magnetocaloric, magnetoelastic, magnetoresistance and other effects.
doi:10.1103/physrevb.88.014423 fatcat:n2xkfr6v55ahhbycu2xexgm6s4