Figure 2
From: Achieving quantum precision limit in adaptive qubit state tomography
Experimental set-up. A pair of horizontally polarised photons are generated via pumping a β-barium borate crystal. One is detected as a trigger and the other is sent through a half-wave plate (HWP), a QWP and a 770λ quartz crystal in between, marked as the state preparation module (green), to change the length and direction of the Bloch vector. After preparation, the photon polarisation is measured by a configuration of QWP2, HWP2 and a polarising beam splitter (PBS), marked as the adaptive measurement module (pink).
