Simulation of electric field-induced ferroelectric domain evolution via first principles effective Hamiltonian

Ferroelectric materials, known for their reversible spontaneous polarization, are essential components in modern devices such as non-volatile memories and sensors. Recent research has increasingly focused on ferroelectric and piezoelectric films for MEMS applications, where substrate-induced in-plane strain plays a crucial role in determining domain structures that are vital for device performance. However, experimentally investigating the three-dimensional structures of these films remains challenging, particularly under applied electric fields.

We employed molecular dynamics simulations with a first-principles-based effective Hamiltonian using an improved code based on the "feram" package developed by Nishimatsu et al. [PRB 78, 104104 (2008)] to explore in-plane strain effects on ferroelectric film domains and their electric field-induced changes. As the computational model, we selected PbTiO3, a typical ferroelectric with perovskite structure. Our findings reveal that cooling-induced stable domains can transform when subjected to z-axis electric fields. Details about the 3D visualization of the ferroelectric domains and structural analyses under field application will be discussed.