Figure 4: Reconstructed density matrices of transmitted states.

Each of the panels above corresponds to a quantum state transmitted from Alice to Bob using superdense teleportation. For each of these states, Bob performed a full two-qubit quantum state tomography in polarization and orbital angular momentum. By correlating his measurements with Alice’s measurement results and numerically performing corrective transformations, Bob reconstructed the density matrix of the state that Alice transmitted. Each panel shows the reconstructed density matrices (for clarity we display only the real parts of these matrices) in the horizontal and vertical polarization basis (H and V) and the right and left orbital angular momentum basis (r and l). The panel labels (a–i) correspond to the letters in Fig. 3 and Table 2, which list the target states and state fidelities.