Abstract
We have measured the magnetization up to 50 kG at low temperatures (1.2-4.2 K) of a series of ZnMn alloys ( ppm Mn). For the alloys studied, the measured magnetization is dominated by impurity-impurity interactions via the indirect Ruderman-Kittel-Kasuya-Yosida (RKKY) potential . These interactions reduce below the Brillouin function appropriate for free spins, and also inhibit the approach to saturation of . In the limit , the measured remains below the free-spin Brillouin function. For the ppm Mn alloys and for , we find , where is the spin of the Mn impurity and . For these alloys we find and erg . The term in may represent a single-impurity (Kondo) effect, while the term clearly represents the effects of the RKKY potential. Scaling behavior is observed for the magnetization once the concentration dependence of the impurity spin is accounted for the in the following way: . However, deviations from scaling of are observed for the 2500-ppm Mn alloy where evidence has been found for additional interactions not of the RKKY type. The scaling behavior of the zero-field magnetic susceptibility is also presented.
- Received 7 February 1974
DOI:https://doi.org/10.1103/PhysRevB.10.2980
©1974 American Physical Society