Fig. 1. The schematic diagram of black phosphorus plasmon strong coupling system：（a）layer-disk-layer distribution of black phosphorus plasmon coupling model，（b）top and side views of the structure，（c）black phosphorus structure and its two lattice directions

Fig. 2. Absorption of black phosphorous disk array：（a）The schematic diagram of the structure of the disk array，the plane wave is irradiated vertically on the structure，（b）the absorption curve when the polarization is 0°（along the Armchair direction）and 90°（Zigzag direction），（c）the electric field distribution at the corresponding absorption peak，（d-e）the absorption spectra at different carrier concentrations when the polarization angle is 0° and 90°，（f）fitting curve of absorption peak changing with carrier concentration，（g-h）the real and imaginary parts of the conductivity along the two lattice directions of the black phosphorus，（i）the anisotropic absorption spectrum of the black phosphorus disk under different polarization angles

Fig. 3. Hybridization of BPSP in continuous black phosphorus layer with BPLSP in black phosphorus nanodisks：（a）and（b）are the absorption spectra obtained by changing the carrier concentration of the continuous black phosphorus layer from 0.5×10¹⁴ cm^-2 to 2.0×10¹⁴ cm^-2，and the polarization is along the two lattice directions of black phosphorus，（c）and（d）are the simulation results of the above corresponding hybridization mode and its fitting curve，in addition，the green line represents the individual BPLSP mode，and the red line represents the individual BPSP mode

Fig. 4. Absorption curve under different carrier concentration and the electric field distribution at the peak：（a）absorption curves when the carrier concentration is 0.6×10¹⁴ cm^-2、0.8×10¹⁴ cm^-2 and 1.0×10¹⁴ cm^-2，respectively，（b）electric field distribution at the two absorption peaks in the three cases

Fig. 5. Anisotropic absorption of the sheet-disk system with different polarization angles：（a）when the carrier concentration of the continuous black phosphorous layer and the black phosphorous nanodisk is set to 0.8×10¹⁴ cm^-2 and 2.0×10¹⁴ cm^-2 unchanged，the absorption spectrum obtained by changing the polarization angle of the plane wave，（b）the absorption curve when the polarization angle is 45°

Fig. 6. The absorption spectrum and curve analysis of the three-mode coupling in the black phosphorus sheet-disk-sheet hybrid system：（a）and（b）are the multi-order absorption spectra obtained by numerical simulation when the polarization is along the two lattice directions，which are generated by the coupling between Upper-layer BPSP，Low-layer BPSP，and BPLSP modes，（c）and（d）are the position of the absorption peak of the hybridization mode and the dispersion relationship when each mode exists alone

Fig. 7. Relationship between incident light with different polarization angles and transmission under compact π-structure of phosphorene：（a）when the carrier concentration of the continuous black phosphorous layer and the black phosphorous nanodisk is set to 0.8×10¹⁴ cm^-2 and 2.0×10¹⁴ cm^-2 unchanged，the absorption spectrum obtained by changing the polarization angle of the plane wave，（b）the absorption curve when the polarization angle is 45°