Abstract: Proposed is a phase shift introduction method, a structure, and a circuit device for eliminating or minimizing a risk associated with dissimilar materials, solving in principle a problem of mixing of a signal current and a control current that occurs due to DC connection of a phase shifter to a signal line, and stably and reliably providing a phase shift that is desired to be introduced without being adversely effected by noise generated by an ambient magnetic field, which is generated due to use of an external power supply. A structure according to the present invention includes a phase shifter 101 and a closed-loop circuit 103 that is directly used for computation or storage, and a quantum phase shift is generated in the closed-loop circuit 103 by using a fractional flux quantum captured by the phase shifter 101 that is DC-separated from the closed-loop circuit 103.