Passive round-robin differential-quadrature-phase-shift quantum key distribution scheme with untrusted detectors<xref rid="cpb_27_10_100309fn1" ref-type="fn">*</xref><fn id="cpb_27_10_100309fn1"><label>*</label><p>Project supported by the Fund from the State Key Laboratory of Information Photonics and Optical Communications (Beijing University of Posts and Telecommunications) (Grant No. IPOC2017ZT0).</p></fn>

Passive round-robin differential-quadrature-phase-shift quantum key distribution scheme with untrusted detectors**

Project supported by the Fund from the State Key Laboratory of Information Photonics and Optical Communications (Beijing University of Posts and Telecommunications) (Grant No. IPOC2017ZT0).

Liu Hongwei, Qu Wenxiu, Dou Tianqi, Wang Jipeng, Zhang Yong, Ma Haiqiang^†

(color online) Passive RRDQPS-QKD scheme. Alice and Bob use a local laser to generate a train of L-pulse independently, which are then encoded onto relative phases of two time-bin r and s by a phase modulator (PM), Bob records the coincidence clicks. LD: laser diode; BS: a 50/50 beam splitter; PM: phase modulator; QC: quantum channel; D1 and D2 in gray box means these two detectors are untrusted.