Be基Ⅱ-Ⅵ族宽带四元合金的晶格参数与带隙参数

Lattice Constant and Energy Gap of Beryllium Based Ⅱ Ⅵ Widegap Quaternaries

分析了三元合金ｂｏｗｉｎｇ参数的计算公式，指出Ｚ值应当为替换原子的价电子数；通过与实验值的比较，将三元合金分为共阳离子型和共阴离子型两类；对共阳离子体系忽略库仑屏蔽作用，库仑屏蔽参数Ｓｃｒ取零，对共阴离子体系具有较强的屏蔽作用，Ｓｃｒ取０．３０．用二元化合物的晶格常数、带隙参数插值计算获得了三元合金的晶格常数、带隙参数．用三元合金的晶格常数、带隙参数插值获得了四元合金的晶格常数、带隙参数，直观地给出了带隙、晶格常数与组分的关系．本文同时修正了Ａ１－ｘ－ｙＢｘＣｙＤ型四元合金带隙的计算公式．

Abstract By analysing the calculation formula for the bowing parameters of ternary alloys, it is found that the quantity Z in the formula should be the number of the valence electrons of the substituted atoms in a ternary alloy. Ternaries can be classified into two types, that is, the common cation type and the common anion type. For the common cation system, the Coulombic screening effect is neglectable, e.g ., the quantity of S cr equals to zero. For the common anion system, the Coulombic screening effect is a bit stronger and can not be omitted, the quantity of S cr is set to be 0.30. Based on the parameters of lattice and energy gap of binaries, the relevant quantities of the ternaries are obtained in an interpolation scheme, and based on the ternary parameters, the relevant quantities of the quaternary are also achieved. The calculation formula for the energygap of quaternary with the type of A 1- x-y B x C y D is corrected in this paper.