采用Bridgman法生长了x为0.1,0.22和0.4的四元稀磁半导体化合物MnxCd1-xIn2Te4晶体.研究了三根晶体中相的形貌、结构、成分和Mn0.1Cd0.9In2Te4晶体中各组元沿轴向和径向的成分分布.晶体生长初始端的组织为α+β+β1,随着生长的进行,形成β相的单相区.在晶锭末端,形成In2Te3类面心立方结构化合物.组分x增大后,MnxCd1-xIn2Te4晶体的吸收边向短波方向移动,禁带宽度则线性增大.磁化率测量结果表明:晶体在高温区的x-1-T曲线服从居里-外斯定律,在低温区(<50K)则表现出顺磁增强现象.
Diluted magnetic semiconductor MnxCd1-xIn2Te4(x=0.1, 0.22 and 0.4) ingots were grown by the Bridgman method. The structure and composition of different
phases and the compositional distribution along the axis and radius of the MnxCd1-xIn2Te4 ingot were analyzed. α+β+β1
structures are formed at the tip of the MnxCd1-xIn2Te4 ingots. Among them, α and β phases are crystallized from the melt while β1
is precipitated from α phase when temperature is below solidus. The content of β phase increases with the growth process, and finally, a pure β phase-region
is formed. At the end of the ingots, an In2Te3-type phase with a fcc structure is crystallized. There exist two distinct interfaces between the different neighbouring
phase-regions. The band gap of MnxCd1-xIn2Te4 shifts towards the high energy side with the increase of x. At higher temperatures(50～300K) the variation of
magnetic susceptibility χ with T in MnxCd1-xIn2Te4 follows the Curie-Weiss (C-W) law. However, a paramagnetic behavior exists at lower temperature (<50K).
The antiferromagnetic exchange of Mn2+ increases with the composition, x.
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