Strain of material w. (111) orientation is asymmetric about center point? Why?

[yzou_ua]

strain of material w. (111) orientation is asymmetric about center point? Why??

My calculation shows an asymmetric strain distribution in InAs/GaAs(111) heterostructure while it is symmetric in InAs/GaAs(001).

Someone could give explanation on it??

 

[hiyok]

How was your calculations done?

 

[yzou_ua]

How was your calculations done?

Since the strain is pointwise scalar, what i did is just to calculate one strain component along a particular direction, such as:
exx along x [100] direction, etc.