Pump free quantum transduction Part I

A distributed quantum computing task involves superconducting computation nodes operating at microwave frequencies, connected by long-distance transmission lines that transmit photons at optical frequencies. Quantum transduction, which coherently converts between microwave and optical (M-O) photons, becomes a critical component of such an architecture. Current approaches are hindered by the unavoidable problem of device heating due to the optical pump. In this work, we propose a pump-free scheme based on a single tin-vacancy (SnV-) center that generates time-bin encoded M-O Bell pairs. Our scheme first creates spin-photon entanglement using a well-established protocol and then maps the spin state to time-bin microwave pulses using a strongly coupled Purcell-enhanced resonator. The microwave retrieval can be heralded by detecting the microwave signal with a three-level transmon, and we analyze the Bell state fidelity and generation probability of our protocol. With our proposed design of a strongly coupled spin-microwave system and the state-of-the-art optical-spin interface, our pump-free scheme demonstrates higher fidelity and probability compared with the current protocol and promises to be a reliable source for M-O Bell state generation for quantum transduction. 

 

This is Part I of a two-part talk. In this talk, we will go through the system step, explain our protocol and point out important figures of merits of the scheme.