Structural properties of plastically deformed SrTiO₃ and KTaO₃

Strontium titanate (SrTiO3, STO) and potassium tantalate (KTaO­3, KTO) are considered incipient ferroelectrics. These perovskites are also remarkably ductile at ambient temperatures, making them excellent candidates for plastic deformation. While this property has been known for over two decades in the case of STO [1], it is worth noting that ductility in KTO has not been previously documented. Here, we present a comprehensive analysis involving diffuse x-ray and neutron scattering data as well as nuclear magnetic resonance (NMR) results aimed to investigate and compare the formation of strain-induced self-organized dislocation structures in plastically deformed STO and KTO. Additionally, we present Raman scattering measurements on plastically deformed KTO, which indicate the emergence of ferroelectric fluctuations induced by severe strain, similar to prior observations in STO [2].

[1] P. Gumbsch et. al., Phys. Rev. Lett. 87, 085505 (2001)

[2] S. Hameed et al., Nat. Mater. 21, 54 (2022).