Fig. 1. (a) A visual representation of the proposed InGaAsP/InP-airgap nano-pillar cavity in three dimensions； (b) Calculated optical mode spectra and corresponding optical bands^[34]

Fig. 2. Scheme of the spectrally multiplexed HSPS fabricated using LNOI technique^[43]

Fig. 3. Experimental setup for spectrally multiplexed HSPS^[43]

Fig. 4. Scheme of a random bit generator with branching paths. (a) Experimental setup, which involved a self-made confocal scanning microscope to stimulate the single photon emitting in the GaN wafer and capture the luminescence from individual photons; (b) HBT configuration, employed to assess the purity of single photons emitted and generate binary random numbers^[45]

Fig. 5. Photon-pair performance of frequency-bin entangled sources. (a) Spatial quantum beating; (b) Real part of density matrices; (c) Imaginary part of density matrices ^[49]

Fig. 6. Cascaded photon entanglement using a single PPLN waveguide. (a) Structure of the PPLN waveguide module; (b) Spectra of correlated photon-pairs generated from the module; (c) and (d) Spectra of co- and cross-polarized Raman photons from the module^[50]

Fig. 7. Experimental setups for (a) Generation of correlated photon-pairs; (b) Characterization of correlated photon-pairs; (c) Characterization of energy-time and time-bin entangled photon-pairs; (d) Coherent manipulation of energy-time entangled photon-pairs; (e) Generation and characterization of frequency-bin entangled photon-pairs^[50]

Fig. 8. (a) Microstructure image; (b) Measured quality curve of the Si₃N₄-microring entangled source^[52]

Fig. 9. (a) Aerial view of the teleportation system based on UESTC backbone network; (b) Scheme of the quantum teleportation system^[54]

Fig. 10. (a) Illustration of entanglement distribution coexisting with classical fiber communication system; (b) QKD experiment setup with 40 km fiber^[55]

Fig. 11. (a) AQR-IC chip and (b) Photon counting system on PCB of a high speed SPAD ROIC^[61]

Fig. 12. Measured (a) PDE; and (b) DCR of a newly fabricated 128×32 InGaAs SPAD array

Fig. 13. Experimental setup of high spatial resolution DWDD ^[71]

Fig. 14. Experimental set-up of quantum memory ^[73]

Fig. 15. (a) Schematic diagram of the optomechanical nanobeam cavity; (b) and (c) Schematic representation of hole's position d and unitary variation of hole dimension Δr in nanobeam cavity; (d) E_y component of optical fundamental mode at telecom band; (e) Displacement field of the corresponding fundamental breathing modeing fundamental breathing mode^[76]

Fig. 16. (a) Crystal structure of 2D CrPS₄; (b) Microscopic image of layered CrPS₄ obtained by mechanical exfoliation; (c) Fabrication processing for CrPS₄ NEMS^[79]