Nonlinear oscillators and circuits can be coupled to reach synchronization and consensus. The occurrence of complete synchronization means that all oscillators can maintain the same amplitude and phase, and it is ofte...Nonlinear oscillators and circuits can be coupled to reach synchronization and consensus. The occurrence of complete synchronization means that all oscillators can maintain the same amplitude and phase, and it is often detected between identical oscillators. However, phase synchronization means that the coupled oscillators just keep pace in oscillation even though the amplitude of each node could be different. For dimensionless dynamical systems and oscillators, the synchronization approach depends a great deal on the selection of coupling variable and type. For nonlinear circuits, a resistor is often used to bridge the connection between two or more circuits, so voltage coupling can be activated to generate feedback on the coupled circuits. In this paper, capacitor coupling is applied between two Pikovsk-Rabinovich(PR) circuits, and electric field coupling explains the potential mechanism for differential coupling. Then symmetric coupling and cross coupling are activated to detect synchronization stability, separately. It is found that resistor-based voltage coupling via a single variable can stabilize the synchronization, and the energy flow of the controller is decreased when synchronization is realized. Furthermore, by applying appropriate intensity for the coupling capacitor, synchronization is also reached and the energy flow across the coupling capacitor is helpful in regulating the dynamical behaviors of coupled circuits, which are supported by a continuous energy exchange between capacitors and the inductor. It is also confirmed that the realization of synchronization is dependent on the selection of a coupling channel. The approach and stability of complete synchronization depend on symmetric coupling, which is activated between the same variables. Cross coupling between different variables just triggers phase synchronization. The capacitor coupling can avoid energy consumption for the case with resistor coupling, and it can also enhance the energy exchange between two coupled circuits.展开更多
In a circuit quantum electrodynamics(circuit QED) architecture, the microwave resonator could be used to couple and probe qubits. The long-range coupling and information transfer between nonlocal qubits can be perform...In a circuit quantum electrodynamics(circuit QED) architecture, the microwave resonator could be used to couple and probe qubits. The long-range coupling and information transfer between nonlocal qubits can be performed via photons trapped in a microwave resonator, promising an effective approach for scaling up solid-state qubits. A series of important advances in the hybrid system composed of a microwave resonator and semiconductor qubits have been achieved in recent years. For instance,with applications of high-impedance microwave resonators, the strong coupling regime between charge/spin qubits and a microwave resonator has been reached. Simultaneously, resonator-based dispersive readout and single-shot readout to probe the qubit state have been further improved due to the increase of the coupling strength. Here, we briefly introduce this hybrid system related to the progress and fruits in achieving the strong coupling between charge/spin qubits in double quantum dots(DQDs)and the resonator, the long-range coupling between qubits, and also the applications of the resonator for qubit state readout.展开更多
基金Project supported by the National Natural Science Foundation of China(No.11672122)
文摘Nonlinear oscillators and circuits can be coupled to reach synchronization and consensus. The occurrence of complete synchronization means that all oscillators can maintain the same amplitude and phase, and it is often detected between identical oscillators. However, phase synchronization means that the coupled oscillators just keep pace in oscillation even though the amplitude of each node could be different. For dimensionless dynamical systems and oscillators, the synchronization approach depends a great deal on the selection of coupling variable and type. For nonlinear circuits, a resistor is often used to bridge the connection between two or more circuits, so voltage coupling can be activated to generate feedback on the coupled circuits. In this paper, capacitor coupling is applied between two Pikovsk-Rabinovich(PR) circuits, and electric field coupling explains the potential mechanism for differential coupling. Then symmetric coupling and cross coupling are activated to detect synchronization stability, separately. It is found that resistor-based voltage coupling via a single variable can stabilize the synchronization, and the energy flow of the controller is decreased when synchronization is realized. Furthermore, by applying appropriate intensity for the coupling capacitor, synchronization is also reached and the energy flow across the coupling capacitor is helpful in regulating the dynamical behaviors of coupled circuits, which are supported by a continuous energy exchange between capacitors and the inductor. It is also confirmed that the realization of synchronization is dependent on the selection of a coupling channel. The approach and stability of complete synchronization depend on symmetric coupling, which is activated between the same variables. Cross coupling between different variables just triggers phase synchronization. The capacitor coupling can avoid energy consumption for the case with resistor coupling, and it can also enhance the energy exchange between two coupled circuits.
基金supported by the National Key Research and Development Program of China(Grant No.2016YFA0301700)the National Natural Science Foundation of China(Grant Nos.61922074,12074368,and12034018)the Innovation Program for Quantum Science and Technology(Grant No.2021ZD0302300)。
文摘In a circuit quantum electrodynamics(circuit QED) architecture, the microwave resonator could be used to couple and probe qubits. The long-range coupling and information transfer between nonlocal qubits can be performed via photons trapped in a microwave resonator, promising an effective approach for scaling up solid-state qubits. A series of important advances in the hybrid system composed of a microwave resonator and semiconductor qubits have been achieved in recent years. For instance,with applications of high-impedance microwave resonators, the strong coupling regime between charge/spin qubits and a microwave resonator has been reached. Simultaneously, resonator-based dispersive readout and single-shot readout to probe the qubit state have been further improved due to the increase of the coupling strength. Here, we briefly introduce this hybrid system related to the progress and fruits in achieving the strong coupling between charge/spin qubits in double quantum dots(DQDs)and the resonator, the long-range coupling between qubits, and also the applications of the resonator for qubit state readout.