Tuning photostriction in (PbTiO${}_3$)${}_n$/(SrTiO${}_3$)${}_m$ superlattices via chemical composition: An $\mathit{\text{ab-initio}}$ study

Light-induced mechanical deformations in single-domain (PbTiO${}_3$)${}_n$/(SrTiO${}_3$)${}_m$ superlattices were simulated using first-principle calculations. By varying the chemical fraction PbTiO${}_3$, we discover that these heterostructures’ photostrictive behavior can be tuned quantitatively and qualitatively. Additionally, we present simple analytical models to explain the calculated deformations and predict a critical PbTiO${}_3$ fraction with no photostriction. In addition to the report in [1], our results present another way for tuning the photostrictive behavior of (PbTiO${}_3$)${}_n$/(SrTiO${}_3$)${}_m$ superlattices, which could be utilized for innovative optomechanical applications.