Low-dimensional ferroelectrics under different electrical and mechanical boundary conditions: Atomistic simulations

Ferroelectric nanodots and infinite wires of Pb(Zr0.4Ti0.6)O₃ alloy under different boundary conditions are investigated via Monte Carlo simulations using an atomistic first-principles-based effective Hamiltonian. These nanosystems all exhibit a spontaneous polarization that points along a nonperiodic direction, for situations close to short-circuit electrical boundary conditions and independently of the epitaxial strain. On the other hand, unusual dipole patterns arise in these systems when they are under open-like circuit conditions. The dependency of these patterns on the nanostructure's dimensionality and strain is further revealed and explained.