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Table 11.1: Entangled State Density Matrix – Raw
ρ raw | 00 〉 | 01 〉 | 10 〉 | 11 〉
| 00 〉 0.151 −0.005 + 0.034i 0.041 + 0.034i −0.003 + 0.005i
| 01 〉 −0.005 − 0.034i 0.369 −0.380 − 0.000i −0.030 − 0.012i
| 10 〉 0.041 − 0.034i −0.380 + 0.000i 0.428 −0.004 − 0.054i
| 11 〉 −0.003 − 0.005i −0.030 + 0.012i −0.004 + 0.054i 0.051
Table 11.2: Entangled State Density Matrix – Corrected for Visibilities
ρ corr | 00 〉 | 01 〉 | 10 〉 | 11 〉
| 00 〉 0.135 −0.006 + 0.040i 0.046 + 0.037i −0.003 + 0.006i
| 01 〉 −0.006 − 0.040i 0.387 −0.431 + 0.000i −0.034 − 0.015i
| 10 〉 0.046 − 0.037i −0.431 − 0.000i 0.449 −0.004 − 0.061i
| 11 〉 −0.003 − 0.006i −0.034 + 0.015i −0.004 + 0.061i 0.029
the fact that the pulses that sweep the first qubit off and the second qubit on
resonance also cause Z-rotations.
11.1.4 Verifying Entanglement – State Tomography
At this point, for either coupling scheme, the qubit pair should be prepared
in a highly entangled state similar to the Bell singlet. To verify the quality of the
created state, one can employ a technique called “Quantum State Tomography”
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