Entangling two distant non‐interacting microwave modes

Abstract

We propose a protocol able to prepare two remote and initially uncorrelated microwave modes in an entangled stationary state, which is certifiable using only local optical homodyne measurements. The protocol is an extension of continuous variable entanglement swapping, and exploits two hybrid quadripartite opto-electro-mechanical systems in which a nanomechanical resonator acts as a quantum interface able to entangle optical and microwave fields. The proposed protocol allows to circumvent the problems associated with the fragility of microwave photons with respect to thermal noise and may represent a fundamental tool for the realization of quantum networks connecting distant solid-state and superconducting qubits, which are typically manipulated with microwave fields. The certifying measurements on the optical modes guarantee the success of entanglement swapping without the need of performing explicit measurements on the distant microwave fields.

Entanglement Thresholds of Doubly-Parametric Quantum Transducers

“…In all of these protocols, the classical average fidelity bounds for the transduced states cannot be surpassed if the transducer fails to achieve quantum operation under our definition. Thus finding the thresholds for when a transducer achieves quantum operation will set the lower bounds for when any of these protocols can succeed or when protocols for networking remote microwave modes over optical links become limited by the transducers at each node [18][19][20][21][22][23].…”

Transferring Einstein-Podolsky-Rosen State Cross Frequency Bands via Cavity Electro-Opto-Mechanical Converters

“…Intra-cavity or itinerant state transfer is a significant ability of cavity EOM converter. Various theoretical and experimental work have been done to explore this feature [5][6][7][8]. These work show transferring single mode quantum state with high fidelity could be achieved via cavity EOM converter from optical regime to microwave regime.…”

Continuous-variable pairwise entanglement based on optoelectromechanical system

“…However, the research of the pairwise entanglement primarily concentrates on DV regime [21][22][23], considering the close relationship between DV and CV entanglement, a question naturally arises: how does the pairwise entanglement behave in CV regime? Indeed, to analyse the pairwise entanglement between CV carrier, like the DV counterpart, suitable platforms are needed, owing to the successful theoretical prediction and experimental realization on entanglement between mechanical mode and electromagnetic fields with different frequency [24][25][26][27][28][29][30][31][32][33][34][35][36], optoelectromechanical system should be the one.…”