HexagonalBN PDMS Aggregated_molecules STO Annealed Permalloy ScanningSpreadingResistanceMicroscopy BismuthVanadate 2d_materials Terrace Insulator Typhimurium FM_KPFM Switching amplitude_modulation cooling Leakage Lattice InorganicCompound Bismuth India PS_LDPE PyroelectricDetector molecular_self_assembly Pyroelectric Iron Platinum Pinpoint PFM TCS Ucl TappingMode ThermalDetectors StrontiuTitanate Nanostructure C_AFM