Extended Data Fig. 5: Atom-photon entanglement fidelity degradation from residual atom-motion entanglement.
From: Parallelized telecom quantum networking with an ytterbium-171 atom array
(a) Illustration of the motion state evolution during REG sequence. The non-commutativity between eiΔk⋅x and \({e}^{-i{H}_{m}\Delta t}\) leads to non-overlapping motion wavefunctions associated to the early (blue) and late (red) time bin. (b) Fidelity degradation from radial and axial atom-motion entanglement as a function of time-bin separation. As our \(\Delta \overrightarrow{k}\) has components along both radial and axial directions, we calculate effects on the overall atom-photon Bell state fidelity from both axial and radial thermal states for different temperatures. The grey dashed line indicates Δt = 2.8μs which we use in our experimental sequence. We expect a ≈ 0.9% fidelity reduction from both radial and axial motion combined.
