Interfacial Strain Calculation: BaTiO3 on SrTiO3

[martinphy]

Hello everyone,
I have a question on the calculation of interfacial strain. If we know the elastic constants of BaTiO3 (1 dimension), how to give a quantitative estimation of the elastic energy per unit cell layer grown with a c-axis orientation on SrTiO3? Thanks very much

 

[BigJDubs]

The calculation of interfacial strain energy in this case is a relatively complex process. Generally, it involves finding the difference between the two materials' elastic constants, and then calculating the strain energy using the equation:E = 0.5*Cijkl*eij*eijwhere Cijkl is the elastic stiffness tensor, and eij is the strain tensor. You will need to use the elastic constants for BaTiO3 and SrTiO3 to calculate the stiffness tensor, and then calculate the strain energy when the two materials are grown together. You will also need to consider the effect of the c-axis orientation on the strain energy. This can be done by calculating the change in strain energy when the two materials are grown with different orientations. Finally, you will need to take into account the effects of surface energy and surface relaxation, which can be calculated using the Lifshitz-Silberberg model. I hope this helps!