Time-bin-encoding-based remote states generation of nitrogen-vacancy centers through noisy channels*
Su Shi-Leia), Chen Lib), Guo Qia), Wang Hong-Fuc), Zhu Ai-Dongc), Zhang Shoua),c)†
       
A sketch of W state generation. H1, H2, H3, and H4 denote the HWP with the action on the photon pulse, respectively. The role of the HWP1, HWP2, HWP3, HWP4 is to perform a σ x operation (| R ⟩↔| L ⟩) on the photon. The optical control sequences and requirement of delay lines are the same as GHZ state generation.