Fig. 4: Conditional entanglement swapping and gate teleportation.
a Circuit diagram for conditional entanglement swapping. The gray circuit elements are used to verify entanglement swapping. b The unconditioned singlet probability on the left side p(SL) shows no oscillations. However, p(SL∣SR) and p(SL∣TR) show pronounced singlet–triplet oscillations. Simulated predictions are shown in the same color. c Comparison of the extracted oscillation frequency vs. repetition number measured on qubits 1 and 2 to the measured hyperfine gradients. The sudden jump in ΔB12 near repetition 200 likely results from frequencies too low to measure properly. d Circuit diagram for conditional gate teleportation. e p(SR) shows only weak oscillations, but p(SR∣SL) and p(SR∣TL) show prominent singlet–triplet oscillations. Simulated predictions are shown in the same color. f Comparison of the extracted entanglement-swap and gate-teleport oscillation frequencies vs. repetition number.
