Circuit apparatus and control method
A circuit apparatus includes: a plurality of parametric oscillators; a magnetic field generator provided for each of the parametric oscillators; a coupler provided for each of the parametric oscillators; a signal generator configured to output a phase-locking signal incident on the parametric oscillator via the coupler and a pump signal incident on the magnetic field generator; and a controller configured to control the signal generator, wherein the parametric oscillator includes a variable element, the magnetic field generator applies a magnetic field to the variable element, the signal generator includes output channels for the phase-locking signal, a number of the output channels being fewer than a number of the parametric oscillators, and the controller controls a phase difference between the phase-locking signal and the pump signal.
1 . A circuit apparatus comprising:
a plurality of parametric oscillators;
a magnetic field generator provided for each of the parametric oscillators;
a coupler provided for each of the parametric oscillators;
a signal generator configured to output a phase-locking signal incident on the parametric oscillator via the coupler and a pump signal incident on the magnetic field generator; and
a controller configured to control the signal generator,
wherein the parametric oscillator includes a variable element,
the magnetic field generator is configured to apply a magnetic field to the variable element,
the signal generator includes output channels for the phase-locking signal, a number of the output channels being fewer than a number of the parametric oscillators, and
the controller is configured to control a phase difference between the phase-locking signal and the pump signal.
2 . The circuit apparatus according to claim 1 ,
wherein the signal generator is configured to output the phase-locking signal on which signals of different frequencies determined for each parametric oscillator are superimposed, and
the signal generator includes one of the output channels for outputting the superimposed phase-locking signal.
3 . The circuit apparatus according to claim 1 ,
wherein one of the output channels for the phase-locking signal and each of the couplers are connected by a transmission line.
4 . The circuit apparatus according to claim 1 ,
wherein one of the output channels for the phase-locking signal and each of the couplers are connected by a transmission line, and a filter is provided at a connection between the transmission line and the coupler, the filter transmitting the phase-locking signal of a predetermined frequency corresponding to a frequency determined for the parametric oscillator corresponding to the coupler.
5 . The circuit apparatus according to claim 1 ,
wherein the signal generator includes output channels for the pump signal, a number of the output channels being fewer than a number of the parametric oscillators.
6 . The circuit apparatus according to claim 1 ,
wherein the signal generator is configured to output the pump signal on which signals of different frequencies determined for each parametric oscillator are superimposed, and
includes one of the output channels for the pump signal for outputting the superimposed pump signal.
7 . The circuit apparatus according to claim 6 ,
wherein one of the output channels for the pump signal and each of the magnetic field generators are connected by a transmission line.
8 . The circuit apparatus according to claim 6 ,
wherein one of the output channels for the pump signal and each of the magnetic field generators are connected by a transmission line, and a filter is provided at a connection between the transmission line and the magnetic field generator, the filter transmitting the pump signal of a predetermined frequency corresponding to a frequency determined for the parametric oscillator corresponding to the magnetic field generator.
9 . The circuit apparatus according to claim 1 ,
wherein the signal generator is configured to output the phase-locking signals of different frequencies determined for each parametric oscillator and a signal on which the phase-locking signals are superimposed, and
the signal generator includes one of the output channels for outputting the superimposed signal.
10 . The circuit apparatus according to claim 9 ,
wherein one of the output channels and each of the couplers are connected by a transmission line.
11 . The circuit apparatus according to claim 9 ,
wherein one of the output channels and each of the couplers are connected by a transmission line, and a filter is provided at a connection between the transmission line and the coupler, the filter transmitting the signal of the frequency determined for the parametric oscillator corresponding to the coupler.
12 . The circuit apparatus according to claim 9 ,
wherein the output channel and each of the magnetic field generators are connected by a transmission line.
13 . The circuit apparatus according to claim 9 ,
wherein the output channel and each of the magnetic field generators are connected by a transmission line, and a filter is provided at a connection between the transmission line and the magnetic field generator, the filter transmitting the signal of the frequency determined for the parametric oscillator corresponding to the magnetic field generator.
14 . The circuit apparatus according to claim 1 ,
wherein the parametric oscillator is a quantum bit, and a state of the quantum bit is controlled by the phase difference.
15 . A control method comprising:
controlling a phase difference between a phase-locking signal and a pump signal in a circuit apparatus that includes a plurality of parametric oscillators, a magnetic field generator provided for each of the parametric oscillators, a coupler provided for each of the parametric oscillators, and a signal generator configured to output the phase-locking signal incident on the parametric oscillator via the coupler and the pump signal incident on the magnetic field generator,
wherein the parametric oscillator includes a variable element, the magnetic field generator is configured to apply a magnetic field to the variable element, and the signal generator includes output channels for the phase-locking signal, a number of the output channels being fewer than a number of the parametric oscillators.
16 . The control method according to claim 15 ,
wherein the parametric oscillator is a quantum bit, and a state of the quantum bit is controlled by the phase difference.
17 . The control method according to claim 15 ,
wherein the phase difference is controlled in the circuit apparatus based on data associating the phase difference with an occurrence probability of a 0 state and a 1 state of a quantum bit of the parametric oscillator, and a desired occurrence probability.