Designer 3D magnetic mesostructures

摘要: Micro Hall probe magnetometry has been used to investigate the magnetisation of various electrodeposited microcrystals. Superconducting tin crystals almost perfect square cuboid shapes exhibit a strong size dependence supercooling superconducting state and, for smallest accessible crystals, crossover mesoscopic regime can be readily explored close their critical temperatures. Experimental results are in good agreement with Ginzburg-Landau simulations using exact experimental parameters. Electroplating cores another material provides unique core-shell structures either two superconductors (S-S’: tin-lead) or core, covered ferromagnetic shell (S-F: tin/lead-nickel). The parameters core Sn-Pb considerably enhanced and superconductivity is detected up 1:16 TSn c . Little-Parks oscillations analysed reveal extent sheath hence utilised measure range proximity effect temperature shell. In S-F structures, field cancellation effects govern overall behaviour. Under certain conditions it was possible switch magnetic response from para(ferro-)magnetic diamagnetic back at finite applied fields. Micromagnetic qualitatively reproduce experimentally observed effects. Applications include guidance memory devices.