MagneticForce Writing PVAC contact HighAcpectRatio UnivCollegeLondon LiNbO3 PolyStylene Butterfly DOE PVA Polyethylene Hexacontane IIT-chennai chemical_compound Chungnam_National_University I-VSpectroscopy Fluoride TempControl Polyvinylidene GaP Phenanthrene KPFM 2d_materials Polyvinylidene_fluoride #Materials Christmas Chemical Vapor Deposition BismuthVanadate Force-distance GalliumPhosphide ContactMode PVAP3HT Varistor PpLdpe