The quantum key distribution(QKD) has been entering the practical application era. Subsequently, hybrid quantum private communication with discrete-variable signals, continuous-variable signals, and classic optical signals becomes inevitable in the practical scenario. In this paper, we experimentally investigated the mutual effects between the discrete-variable QKD(DVQKD) and the continuous-variable QKD(CVQKD) via a fiber channel. The experimental results show that the DVQKD will be influenced by the continuous-variable quantum signals and classic optical signals, while the CVQKD is not sensitive to the discrete-variable quantum signals.
LIU WeiQiPENG JinYeWANG ChaoCAO ZhengWenHUANG DuanLIN DaKaiHUANG PengZENG GuiHua
A quantum access network has been implemented by frequency division multiple access and time division multiple access, while code division multiple access is limited for its difficulty to realize the orthogonality of the code. Recently,the chaotic phase shifters were proposed to guarantee the orthogonality by different chaotic signals and spread the spectral content of the quantum states. In this letter, we propose to implement the code division multiple access quantum network by using chaotic phase shifters and synchronization. Due to the orthogonality of the different chaotic phase shifter, every pair of users can faithfully transmit quantum information through a common channel and have little crosstalk between different users. Meanwhile, the broadband spectra of chaotic signals efficiently help the quantum states to defend against channel loss and noise.
Temporal cavity solitons(CSs) have excellent properties that can sustain their shape in a temporal profile and with a broadband, smooth-frequency spectrum. We propose a method for controllable frequency line spacing soliton formation in a microresonator using two continuous-wave(CW) pumps with multi-free-spectral-range(FSR) spacing. The method we propose has better control over the amount and location of the solitons traveling in the cavity compared to the tuning pump method. We also find that by introducing a second pump with frequency N FSR from the first pump, solitons with N FSR comb spacing can be generated.