BTO MagneticArray FAFailureAnlaysis exfoliate flakes Conductive AFM Hole cannabidiol LateralPFM BiVO4 Ucl SurfaceChange WPlug Conductivity UnivOfMaryland Bismuth heterojunctions Ni81Fe19 NCM\ Foil HDD Cross-section PvdfBead NusEce LaAlO3 ElectrostaticForceMicroscopy Switching Heating TPU ForceVolume Piezo Hair PinPointMode Titanate atomic_layer