Extended Data Fig. 5: Polarization stabilization.
From: Entanglement of nanophotonic quantum memory nodes in a telecom network
a, Experimental setup used to measure and stabilize the change of the DOP introduced by the 35 km fibre link. A linearly polarized lock laser can be launched into the fibre link. After the fibre link, the DOP is measured using a polarimeter. A fibre-based polarization controller is used to stabilize the DOP. b, DOP measurement during 5 hours through the 35 km fibre link, not using polarization stabilization. During the measurement period, the initially linearly polarized light traces out the full phase space of the DOP. c, DOP during 5 days of nuclear-nuclear entanglement generation, with polarization stabilization enabled. The DOP can be stabilized at around χ = ψ = 0.
