Figure 1
From: Experimental on-demand recovery of entanglement by local operations within non-Markovian dynamics
Open-loop set-up.
(a) Conceptual scheme. Qubits A and B are prepared in the Bell state |Ψ−〉. Qubit B interacts stroboscopically with the environment through the 4 random phases x(tk). The noise induced by the environment can be compensated either with a rephasing unitary Ucorr or with an echo-pulse unitary Uecho = σx. Ef: entanglement of formation measurement. (b) Experimental implementation. LC: liquid cristal retarder, HWP: half-wave plate, QWP: quarter-wave plate, PBS: polarizing beam-splitter, SPAD: single photon avalanche photodiode, C: coincidence counting electronics.
