Fig. 2: Representative ferroelectric states of PbTiO3/SrTiO3 superlattices.
From: Giant voltage amplification from electrostatically induced incipient ferroelectric states
a–d Multi-OOP state for η = −1% of a 6/6 superlattice (a), mono-IP state for η = 1% (b), and mixed states for η = 0.1% (c) and 0.4% (d). Arrows represent local polarization in the xz plane and the colour scale corresponds to the polarization along y. The zero of strain corresponds to the lattice constant of bulk STO (3.901 Å).
