Patent ID: 11955929
Assignee: NEC CORPORATION
Field: Basic communication processes (Electrical engineering)
Classification: CPC H  G | IPC G  H

Claim 13:
14. A control method comprising:
making an oscillator perform parametric oscillation by feeding a DC (Direct Current) current having a first current value and an AC (Alternating Current) current having a predetermined frequency to a magnetic-field generating circuit, the magnetic-field generating circuit being a part of the oscillator; and
then, reading out, by a reading-out circuit, an internal state of the oscillator by feeding a DC current having a second current value different from the first current value to the magnetic-field generating circuit, wherein
the oscillator comprises a resonator and the magnetic-field generating circuit, the resonator comprising a loop circuit and a capacitor, the loop circuit comprising a first superconducting line, a first Josephson junction, a second superconducting line, and a second Josephson junction connected in a ring shape, and the magnetic-field generating circuit being configured to apply a magnetic field to the loop circuit,
the capacitor and the loop circuit are connected in a ring shape to constitute a ring circuit in the resonator,
the ring circuit comprising the capacitor and the loop circuit is connected to the read-out circuit through a filter, the filter being configured to restrict transmission of a signal in a predetermined frequency band,
a transmittance of the filter for a signal having a first frequency is set to a value lower than that of the filter for a signal having a second frequency,
the first frequency is a first resonance frequency of the resonator determined according to magnitude of a magnetic flux that passes through the loop circuit when the DC current having the first current value flows through the magnetic-field generating circuit, and
the second frequency is a second resonance frequency of the resonator determined according to magnitude of a magnetic flux that passes through the loop circuit when the DC current having the second current value flows through the magnetic-field generating circuit.