Fig. 3: Quantum state tomography (QST).
From: Deterministic Bell state measurement with a single quantum memory
a The pulse sequence of QST. An arbitrary state is mapped to the \({\left|0\right\rangle }_{{\rm{N}}}\) state and repeatedly read out by \({E}_{y}\) resonant red laser (100 nW). The real part of the QST b after Bell state generation, c after the CNOT gate, and d after the Hadamard gate. The basis labeled \(\pm 1,\pm 1\) for each state corresponds to the \({\left|\pm 1,\pm 1\right\rangle }_{{\rm{e}},{\rm{N}}}\) state, respectively. Note that the RF-pulse polarizations for the final state (d) are optimized, slightly increasing the fidelity compared with the others (b, c). For each state, the obtained fidelity \(F\) exceeds 90%.
