ferromagnetic NUS_Physics Ananth FrictionalForceMicroscopy FM-KPFM India Edwin Filter Boron frequency_modulation NiFe LifeScience MechanicalProperty AtomicSteps FastScan #EC Implant HOPG Biofilm Materials LateralPFM ScanningKelvinProbeMicroscopy ConductiveAFM temp_control Leakage mono_layer Ca10(PO4)6(OH)2 Growing Graphene SetpointMode Au111 NCM Electrode Scratch OpticalWaveguides