Molecular-dynamics investigation on polarization retention of barium titanate nanofilm arising from ordered oxygen vacancy

Abstract

-Molecular-dynamics simulations have been carried out to investigate the electric hysteresis of barium titanate nanofilm containing oxygen vacancy ordering array parallel to the {101} crystal plane. The results obtained show a significant weakening of polarization retention from non-zero value to zero as the size of the array was reduced to a critical level, which was attributed to the formation and motion of head-to-head domain wall structure under external field loading process. By comparing with materials containing isolated oxygen vacancies, it was found that the zero retention was due to the oxygen vacancy ordering array rather than to the concentration of oxygen vacancy.

Size-dependent brittle-to-ductile transition in GaAs nano-rods

“…The stress tensor is calculated by the classical virial formula and the system temperature is controlled at 300 K by the Nosé Hoover thermostat [30,31]. All simulations are carried out by using a modified version of the DL_POLY package, which can also be applied to predict ferroelectric behaviors of barium titanate [29,32].…”

Investigation of fatigue behavior of Pb(Zr0.45Ti0.55)O3 thin films under asymmetric polarization switching

“…•• -rich region may lead to, for example, the formation of an internal electric field, 21,22) and the reduction of the electrostatic potential well for the trapping of electronic charge carriers at the defect sites. [23][24][25] Although there are a large number of experimental and theoretical results supporting and contradicting these scenarios, the generation and migration of oxygen vacancies still require more investigation owing to their complexity.…”