ABSTRACT
Superconductivity is characterized by two critical lengths, the London penetration depth, λ L (T), and the coherence length, ξ(T), so nanowires may have at least one dimension below one of these characteristic lengths. Superconducting nanowires are mesoscopic one-dimensional (1D) objects if the diameter is smaller than ξ. Consequently, nanostructuring superconducting materials may alter the superconducting properties, quantum fluctuations may dominate and show up effects that are not known from the respective bulk materials, e.g., size-dependent breakdowns of superconductivity or enhanced transition temperatures, T c . As λ and ξ increase towards T c , these effects may be prominent around T c . Besides the fundamental questions concerning the mechanisms of superconductivity, there are several possible applications of superconducting nanowires as interconnects, sensitive detectors of magnetic fields (SQUIDs), single photons (SNSPDs), microkelvin temperature variations (nanoSQUIDs), and quantum computer processors for hosting of qubits with improved stability. Superconducting nanowires can be made from metallic low-T c materials as well as from ceramic high-T c superconductors, and several different approaches to fabricating them are described in the literature, including patterning techniques, templating, and spinning processes. The latter techniques, solution blow-spinning, and electrospinning enabled a fully new class of superconducting materials, called fibrous non-woven fabrics with entirely new properties and possible applications.
