oxide_layer Hysteresys FM-KPFM Boron Polyvinylidene Sphere Crystal ring shape InsulatorFilm NtuEee EFM Iron GaAs Piezoelectric Non-ContactMode 2-vinylpyridine BiasMode conductive Force-distance Spain 2d_materials frequency_modulation NusEce Film Jason Inorganic_Compound fifber ThermalDetectors Ni81Fe19 Chrome mono_layer Techcomp ReflexLens MfmAmplitude TransitionMetal