self-assembly KPFM biocompatible Piranha KAIST SingleCrystal light_emitting AtomicSteps ShenYang mono_layer Polyvinylidene_fluoride BTO UnivCollegeLondon ItoGlass NTU BaTiO3 Polymer hard_disk MolybdenumDisulfide Change MfmAmplitude neodymium_magnets TempControl Ucl Memory MembraneFilter TransitionMetal LightEmission FrictionalForceMicroscopy PatternedSapphireSubstrat Genetic Hysteresys IMT_Bucharest Ferrite non_contact