Fig. 1. Schematic of OAM multiplexed CV entanglement based on FWM process. (a) Energy level diagram of double-Λ scheme in the D1 line of ⁸⁵Rb; (b) OAM multiplexed FWM process

Fig. 2. Experimental layout for the enhancement of channel number of OAM multiplexed entanglement

Fig. 3. Images of output fields carrying BG modes with l varying from -14 to 14

Fig. 4. The smallest symplectic eigenvalues υ and intensity gains of the OAM multiplexed FWM process with l varying from -14 to 14