Parametrically-mediated Dissipative Entanglement Generation

Dissipative state preparation provides a powerful alternative to traditional gate-based state preparation protocols. Rather than generating the desired state through a sequence of unitary operations, dissipative protocols engineer always-on interactions with the environment such that the system autonomously converges to the desired state. Such an approach allows improved robustness to initialization errors and decoherence. Nonetheless, dissipative state preparation methods realized thus far have the limitation that the preparation time and error are anti-correlated, meaning that accurate preparation requires long stabilization times. In this talk, I will present a novel scheme which makes use of parametric qubit-qubit and qubit-resonator interactions to avoid this issue. This scheme allows high-fidelity preparation of arbitrary maximally-entangled two-qubit states with stabilization times in the few hundred nanosecond range. Uniquely, it also enables continuous in-situ control of the target state in a specified parity manifold. I will discuss the robustness of the scheme to experimental imperfections and qubit decoherence, and an implementation which is readily achievable with current circuit-QED technology.