HafniumDioxide dichalcogenide STM Korea 3-hexylthiophene PiezoelectricForceMicroscopy Calcite Multiferroic_materials SSRM Graphite Memory TemperatureControl temperature_control Edwin Sphere 2-vinylpyridine Lanthanum_aluminate Mfm strontiu_titanate Strontium C60H122 NUS sputter Indent dielectric trench Fluoride PVAP3HT chemical_compound PANI Fujian FrictionForce University_of_Regensburg Switching AmplitudeModulation GlassTemperature