dichalcogenide LiquidCrystal FrictionalForce HOPG DataStorage MagneticArray AtomicLayer Christmas BCZT Magnets Tin sulfide Polyvinylidene_fluoride Optical small_scan OrganicCompound IIT-chennai Ucl kelvin probe force microscopy Modulus align TipBiasMode NUS_Physics Hair PolymerPatterns PVAC Semiconductor hard_disk_media molecules Workfunction Permalloy CrossSection Conductivity C_AFM HBN biocompatible