Nanoscale Superconductivity: physics and applications
Conventional superconductivity in bulk objects is characterized by three phenomenological features: zero resistivity, perfect diamagnetism ( Meissner effect) and energy gap in the excitation spectrum. In this paper we demonstrate that these attributes of superconductivity do not apply to ultra-small objects governed by the essentially nanoscale phenomenon which is quantum fluctuations. The observation results in fundamental limitations of utilization of superconducting elements in nanoelectronic circuits. However, together with this rather pessimistic conclusion, the indicated size phenomena lead to a new class of nanoscale devices and applications.