Superconducting quantum nano-circuits

Superconducting circuits are described by a small number of macroscopic variables and behave as simple quantum mechanical systems. They can be manufactured and integrated by extending micro-electronics techniques with suspended masks and shadow evaporation techniques. Superconducting circuits can be designed to study novel quantum phenomena and explore some of their applications. In this paper, the physics of some superconducting qubits circuits (phase and coupled charge-phase qubits) is reviewed. Other interesting applications involving quantised superconducting pumps and the current-phase relation of Josephson rhombi networks are also presented. Presently, applications of superconducting circuits to quantum computing are limited by decoherence phenomena. Prospects in material development and circuit integration to overcome these difficulties are also discussed in this review.