Spin-glass ordering in amorphous Tb-Cr alloys

This paper discusses amorphous TbxCr100-x alloys (x =16, 28.5, 43, and 59 a t. %) obtained by quenching from the vapor phase. It is found that the stru cture of the alloys is heterogeneous: the coexistence of two amorphous phas es, characterized by different short-range order, is observed. The short-ra nge order of these phases qualitatively corresponds to the structure of pur e components (Cr or Tb). In the low-temperature region, the alloys transfor m to the spin-glass state. It is established that the transition temperatur es to the spin-glass state depends on the composition linearly, increasing as the terbium concentration increases. It is shown that the magnetic prope rties of amorphous Tb-Cr alloys are determined by the random magnetic aniso tropy associated with the Tb atoms. (C) 1999 American Institute of Physics. [S1063-7834(99)02307-2].