Dynamic Control of Piezoelectricity Enhancement via Modulation of the Bulk Photovoltaic Effect in a BiFeO ₃ Thin Film

Piezoelectricity, which is an electromechanical effect induced by conversion between mechanical and electrical energy, one of the key functionalities in ferroelectric oxides. Traditionally, structural engineering synthesis via a variety processing control parameters has been well-established route to host so-called morphotropic phase boundaries for enhancing piezoelectricity. However, this involves dealing with synthetical complexity difficulties strictly controlling structures defects. Instead, simple situ control, here, critical pathway light-induced piezoelectricity enhancement its dynamic unveiled BiFeO3/DyScO3 thin film implementing in-plane geometry operation, allowing modulation bulk photovoltaic effect. A series length-dependent piezoresponse force microscopy conductive atomic microscopy-based measurements under illumination reveals strong influence on photocurrent photovoltage, consequently revealing maximum eightfold increase effective piezoelectric coefficient, dzz. Light polarization dependent show sinusoidal behavior closely linked variations, leading further threefold Temporal decay reveal persistent enhanced after removal illumination, associated reemission photocarriers trapped sub-levels. These results pave way compatible films multifunctional nano-optoelectronics.