Laser Physics
Deterministic high-dimensional quantum remote implementation via hybrid photonic encoding
Qi-Qi Dong, Junqiang Wang
Abstract
Abstract Remote implementation of high-dimensional quantum operation is pivotal for advancing quantum communication and distributed computing. Here, we propose a deterministic protocol capable of performing arbitrary four-dimensional unitary operations between two spatially separated nodes. The scheme utilizes hybrid encoding in both polarization and spatial degrees of freedom, which not only conserves quantum resources but also leverages the scalability of high-dimensional photonic systems. A key feature of the protocol is the use of weak cross-Kerr nonlinearities combined with X -quadrature homodyne detection. This design significantly reduces the reliance on strong nonlinear interactions and enhances robustness against photon loss. By performing classical feed-forward operations conditioned on coherent-state measurement outcomes, our approach ensures deterministic execution and high operational fidelity. Importantly, the protocol avoids the need for complex ancillary entanglement by relying solely on linear optics and simplified measurements. Due to the use of mature optical components and a loss-resilient architecture, numerical simulations under realistic experimental conditions indicate a high success probability (≈1) of this scheme. These advantages highlight the practicality and resource efficiency of our method, making it well-suited for the implementation of high-dimensional quantum communication protocols with current photonic technologies.