hetero_structure MfmAmplitude Singapore Forevision PVAC Mapping SICM Insulator self_assembly ULCA SiWafer Ram HydroGel Regensburg Hair Chungnam_National_University Optical Photovoltaics Wildtype lithography SingleCrystal PVA neodymium_magnets GlassTemperature Optoelectronic PyroelectricDetector ForceVolume LDPE Lateral_Force_Microscopy temp_control GaP GaN Magnets Collagen PolyvinylAcetate