Low-temperature AC susceptibility and specific heat measurements have been performed to study the influence of the concentration of charge carriers on the ferromagnetic phase transition of Pb/sub 1-x-y/Sn/sub y/Mn/sub x/Te for various compositions (0.005>or=x>or=0.1, 0.4>or=y>or=1.0). A critical carrier density above which a ferromagnetic transition can take place is observed. This behavior is also reflected in the Curie-Weiss temperature Theta obtained from high-temperature susceptibility data. A simple modified RKKY mechanism for semiconductors is proposed in which carriers from two valence bands located in different regions of the Brillouin zone contribute. The effect of a finite mean free path of the carriers is taken into account. This model gives excellent agreement with the data is obtained without the use of a fitting parameter.
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机译：已经进行了低温AC敏感性和比热测量，以研究各种组成下电荷载流子浓度对Pb / sub 1-xy / Sn / sub y / Mn / sub x / Te铁磁相变的影响（ 0.005>或= x>或= 0.1，0.4>或= y>或= 1.0）。观察到临界载流子密度，高于该载流子密度会发生铁磁跃迁。该行为也反映在从高温磁化率数据获得的居里-魏斯温度Theta中。提出了一种简单的改进的RKKY半导体机制，其中来自位于布里渊区不同区域的两个价带的载流子起作用。考虑到载流子的有限平均自由程的影响。该模型与无需使用拟合参数即可获得的数据非常吻合。
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