Measurement-device-independent quantum secret sharing
  Measurement-device-independent entanglement witness (MDI-EW) will always give an affirmative certification for witnessing entanglement with untrusted measurement apparatuses. Using the MDI-EW method, we propose a measurement-device-independent quantum secret sharing (MDI-QSS) protocol that Charlie can securely distribute a key between the two agents Alice and Bob. A tight bound for collective attacks can provide good bounds on the long-distance MDI-QSS with source flaws. Then we show through numerical simulations that using single-photon source a secure QSS over 136 km can be achieved. 
Xiuqing Yang, Kejin Wei, Haiqiang Ma, Shihai Sun, Hongwei Liu, Zuohan   Li, Zhenqiang Yin, Yungang Du, Lingan Wu
quant-ph