Josephson persistent-current qubit

A qubit was designed that can be fabricated with conventional electron beam Lithography and is suited for integration into a Large quantum computer. T he qubit consists of a micrometer-sized Loop with three or four Josephson j unctions; the two qubit states have persistent currents of opposite directi on. Quantum superpositions of these states are obtained by pulsed microwave modulation of the enclosed magnetic flux by currents in control Lines. A s uperconducting flux transporter allows for controlled transfer between qubi ts of the flux that is generated by the persistent currents, leading to ent anglement of qubit information.