Transport and Magnetic Measurements on Bi₂Sr₂CaCu₂O₈ Nanowire Networks Prepared Via Electrospinning

Superconducting nanowire networks of Bi₂Sr₂CaCu₂O₈ (Bi-2212) were fabricated by means of the electrospinning technique. The electrospinning technique enables the growth of long nanowires up to the millimeter range, whereas the diameter of the nanowires can be controlled by the processing parameters. The resulting materials are fabric-like structures of about 4 × 4 mm² in size, showing a large number of interconnects and junctions between the nanowires. The resulting nanowires are of granular nature with a grain size similar to the wire thickness of about 100-150 nm, and the diameter of the nanowires is about 100-200 nm as determined by electron microscopy. As these nanowire networks are a new class of superconducting materials, we studied the electric transport properties (resistance, U/I characteristics) of such nanowire networks in applied magnetic fields (0-12 T). Measurements of the susceptibility and magnetization hysteresis loops were performed by SQUID magnetometry as well. Possible applications of such nanowire networks are discussed.