Study of the Interplay of Reentrant Ferromagnetism and Ce-spin Fluctuation in Sm1-x-yGdxCeyMn2Ge2
To clarify the effects of strong host magnetic fields on Ce-spin fluctuation, we have carried out magnetic, transport, and x-ray absorption studies on Sm_1-x-yGd_xCe_yMn_2Ge_2 compounds. The undoped SmMn_2Ge_2 compound shows reentrant ferromagnetism. Upon cooling, it successively reaches a ferromagnetic (FM) phase above 300 K, an antiferromagnetic (AFM) phase at T_t2\approx 150K, and a FM phase again at T_t3\approx 105K. The magnetic susceptibility results indicate that substitution of Ce for either Sm or Gd expands the AF-phase region (T_t3\leq T \leq T_t2) and shifts it to the lower temperature side. Such effects appears stronger in the Ce for Sm substitution process than the Ce for Gd substitution process. The Ce L_3-edge results indicate that Ce is almost trivalent in this compound series. The lattice parameter a is found to increase with y. The temperature dependent resistivity data show essentially a metallic behavior for the compounds. The correlation between these results will be discussed.
Presented at the March Meeting of the American Physical Society, St. Louis, MO, March 20-24, 1996.
Physics and Astronomy
Bulletin of the American Physical Society
G. Liang, B.X. Tang, C.H. Zhou, R. Palma, M. Croft, K. Mochizuki, and J.T. Markert, 1996. Study of the Interplay of Reentrant Ferromagnetism and Ce-spin Fluctuation in Sm1-x-yGdxCeyMn2Ge2. Bulletin of the American Physical Society 41, No. 1, 689.