Fig. 1. Schematic of quadripartite quantum steering schemes. (a) One linear beam splitter combines with four-wave mixing system; (b) two linear beam splitters combine with four-wave mixing system

Fig. 2. Quantum steering parameter between any two modes versus gain G(η1=η2=0.8,gc=3.9,T1=0.5)

Fig. 3. Joint steering between one mode and different mode combinations versus gain G(η1=η2=0.8,gc=3.9,T1=0.5). (a) Quantum steering parameter between one and the other two modes; (b) quantum steering parameter between one mode and the remaining three modes

Fig. 4. Quantum steering parameter between single modes versus transmittance T₂ and gain G(η1=η2=0.8,gc=3.9,T1=0.5). (a) Steering of mode A^ to mode F^; (b) steering of mode F^ to mode A^; (c) steering of mode B^ to mode E^; (d) steering of mode E^ to mode B^

Fig. 5. Quantum steering parameter between any two modes versus transmittance T2(η1=η2=0.8,gc=3.9,T1=0.5,G=3)

Fig. 6. Quantum steering parameter between one and the other two modes versus transmittance T2(η1=η2=0.8,gc=3.9,T1=0.5,G=3). (a)(b) (1+1)-mode quantum steering between mode A^ and mode F^; (c)(d) (1+1)-mode quantum steering between mode B^ and mode E^; (e) no steering between single modes

Fig. 7. Quantum steering parameter between one mode and the remaining three modes versus transmittance T2(η1=η2=0.8,gc=3.9,T1=0.5,G=3)