A charge qubit is a superconducting qubit for quantum computing whose basis states are charge states (ie. states which represent the presence of absence of charge). A charge qubit is formed by a tiny superconducting island (also known as a Cooper-pair box ) coupled to a Josephson junction, which is attached to a superconducting reservoir.

External Link

Nakamura, Y., Yu. A. Pashkin, and J. S. Tsai, 1999, Coherent control of macroscopic quantum states in a single-Cooper-pair box, Nature 398, pp. 786-788