Fig. 3: Measurements of the memory lifetime.
From: One-hour coherent optical storage in an atomic frequency comb memory
a, c Decay of the spin-wave AFC echo with the CPMG and KDDx sequences, respectively. The two DD sequences reach their longest storage lifetime of 52.9 ± 1.2 and 33.3 ± 1.1 min with a period τ = 100 ms. b The decay of the echo intensity using CPMG with τ = 100 ms versus the storage time. Some of the single-shot oscilloscope traces of the read out signals are included. Each data point is averaged four times. The error bars indicate one standard deviation of the echo area.
