Fig. 1. System algorithm block diagram.

Fig. 2. Attractor diagram of the new five-dimensional entangled chaotic system.

Fig. 3. Schematic diagram of dynamic probabilistic shaping.

Fig. 4. Fourth-order Rubik’s cube encryption concept diagram.

Fig. 5. Rubik’s cube encryption example diagram.

Fig. 6. Experimental setup. DSP, digital signal process; AWG, arbitrary waveform generator; MZM, Mach–Zehnder modulator; EDFA, erbium-doped fiber amplifier; PS, power splitter; DL, delay line; VOA, variable optical attenuator; PD, photodiode; MSO, mixed-signal oscilloscope; OLT, optical line terminal; ONU, optical network unit.

Fig. 7. BER performance of DPS-CAP signals in 7-core fiber.

Fig. 8. BER curves of encrypted DPS-3D-CAP and encrypted 3D-CAP in 7-core fiber at the same bit rate.

Fig. 9. BER measurements with a tiny change in initial value.