Unlocking Static Polarization and Strain Density Waves in Perovskites by Softening a Hidden Antiferrodistortive Tilt Gradient ModeRemoveYajun Zhang, Devesh R. Kripalani, Xu He, Konstantin Shapovalov, Jiyuan Yang, Hongjian Zhao, Shi Liu, Huadong Yong, Xingyi Zhang, Jie Wang, Kun Zhou, and Philippe GhosezPhys. Rev. Lett. 137, 086101 (2026)
