Quantum computing is at an exciting time, with practical quantum processors coming closer to experimental realization. Yet a major challenge in building a practical quantum computer is to generate and manipulate interactions between its many components. Superconducting (SC) qubits are promising candidates not only because they have strong coupling and high-fidelity readout, but also for allowing versatile parametric control that can realize different effective interactions at will, which might be difficult to achieve through other means. In this thesis, we start from the simple example of parametrically flux modulated SC qubit and demonstrate its application towards quantum communication between remote SC modules. We then move on to discuss the parametric modulation of the light-matter interaction strength, where we introduce a novel SC tunable coupler device that allows for the direct dc-flux control of qubit-qubit or qubit-cavity coupling strength without sacrificing qubit coherence, as well as the convenient realization of blue- and red-sideband interactions through appropriate choice of parametric flux-modulation frequency. By engineering the dissipative system-environment interactions through sophisticated parametric control of this tunable coupler device, we achieve the autonomous stabilization of arbitrary qubit states, in a manner akin to laser cooling in atomic physics. Finally, we present our on-going experimental effort of extending the idea of autonomous stabilization to autonomous quantum error correction, an important step towards the ultimate realization of universal quantum computer.




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