Table 1

Summary of DFS data for the four Bell states, before and after collective decoherence (in the 17° basis). TheF out–pure andF out–init columns list the fidelity of the final state with the target Bell state and with the experimentally produced initial state, respectively; theF theory column lists the theoretically expected value; and the F out–theorycolumn lists the fidelity of the final state with the theoretical prediction.

Bell stateFout–pure*Fout–init*FtheoryFout–theory*
HH + VV0.51 ± 0.030.54 ± 0.040.51.00 ± 0.02
HH − VV0.35 ± 0.020.34 ± 0.020.33 ± 0.010.98 ± 0.02
HV + VH0.54 ± 0.020.53 ± 0.020.52 ± 0.020.99 ± 0.02
HV − VH0.97 ± 0.041.00 ± 0.0410.97 ± 0.04
  • * Uncertainties due to counting statistics.

  • Uncertainty due to a 0.5° uncertainty in the basis orientation θ of the decohering elements. From Fig. 1, we see that ψ+ is most affected, whereas φ+ and ψ are totally unaffected.