semifluorinated alkane DLaTGS Polytetrafluoroethylene Polypropylene cross section FM-KPFM Semiconductor AmplitudeModulation Wonseok Force-distance Glass CalciumHydroxyapatite GlassTemp MultiferroicMaterials Logo StyreneBeads BismuthFerrite CNT Ni-FeAlloy organic_polymer Insulator PhaseChange Gold SoftSample polyvinyl acetate Optoelectonics PMNPT Non-ContactMode SurfaceOxidation molecules Polyurethane OpticalWaveguide Pore Nanostructure Iron