Unidirectional reflectionlessness in a non-Hermitian quantum system of surface plasmon coupled to two plasmonic cavities. - De-Xiu Qiu; Ruiping Bai; Cong Zhang; Li-Fang Xin; Xin-Yu Zou; Ying Qiao Zhang; Xing Ri Jin; Chengshou An; Shou Zhang (Quantum Inf. Process., 2019)