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We propose a non-cryogenic optical quantum memory for noble-gas nuclear spins based on the Atomic Frequency Comb (AFC) protocol. Owing to the hours-long coherence lifetimes of the noble-gas spins and the large bandwidth provided by the AFC independently of the optical depth, we estimate a time-bandwidth product of up to 9. 7 10^15 for a realistic experimental configuration. Leveraging on this long-lived multimode memory, we propose a ground-based quantum repeater that enables entanglement distribution over distances up to 2300 \ km with only 8 elementary links. Finally, we discuss how these quantum memories can enhance rates in space-based quantum communication.
Barbosa et al. (Tue,) studied this question.