LateralPFM self-assembly PatternedSapphireSubstrat self_assembly alkanes GlassTemperature OpticalModulator temperature controller AFM CuSubstrate HexacontaneFilm Subhajjit FrictionForce TempControl MonoLayer Strontium Inorganic_Compound Annealed FrequencyModulation PVAC Electical&Electronics Beads Ceramics hard_disk PinPointMode amplitude_modulation Piezoelectric Titanate HOPG Materials nanobar hard_disk_media PhthalocyaninePraseodymium self-assembled_monolayer conductive Resistance