AtomicSteps FloppyDisk Au111 SKPM PDMS pinpoint mode Topography FrictionalForce Floppy HACrystal hard_disk ScanningSpreadingResistanceMicroscopy GaN Wildtype C_AFM Wang TungstenDeposition SetpointMode Galfenol PolyimideFilm Hafnium_dioxide dielectric_trench Ucl Litho Granada Composition single_layer UnivCollegeLondon layers Stiffness ferromagnetic Hafnia FuelCell Iron ForceDistanceSpectroscopy