VortexCore Array epitaxy KAIST SetpointMode Protein MonoLayer Non-ContactMode TriGlycineSulphate Force-distance HiVacuum Typhimurium Dr.JurekSadowski Transparent CopperFoil Polytetrafluoroethylene CP-AFM PANI FrictionalForceMicroscopy Ferroelectric Chungnam_National_University heterojunctions ReflexLens CastIron Graphene C36H74 PvdfBead vertical_PFM Growth Implant Granada Sperm NanoLithography LateralForceMicroscopy kelvin probe force microscopy