Tuning photostriction in (PbTiO₃)_(n)/(SrTiO₃)_(m) superlattices via chemical composition: An textit{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.