Fig. 1. Schematic diagram of the PTLD chip structure.

Fig. 2. Test results of the PTLD. (a) Self-excited emission spectrum. (b) Free-running power curve.

Fig. 3. (a) Schematic diagram of the PFF-SBC. (b) Schematic diagram of the conventional SBC and (c) schematic diagram of the PFF-PTLD. AL, aspherical lens; HWP, half-wave plate; PBS, polarization beam splitter; RG, reflection grating; TG, transmission grating; TL, transform lens; OC, output coupling mirror.

Fig. 4. Beam distribution of the PFF-SBC at a current of 1.6 A. (a) Beam spot profile before TG diffraction and (b) beam spot profile after TG diffraction.

Fig. 5. Spot profiles of the PTLD with different polarization states at different currents.

Fig. 6. Beam quality of different polarization states in direction x.

Fig. 7. (a) Power and ratio of TM polarization state power of PTLD versus current. (b) Comparison between PFF-SBC and conventional SBC in diffraction efficiency of TG. (c) Comparison between PFF-SBC and conventional SBC in combined efficiency.

Fig. 8. (a) Variation relationship of output power and brightness of PFF-SBC versus current. (b) Output spectrum at a current of 1.6 A. (c) Variations of beam quality with current based on PFF-SBC.

Fig. 9. (a) Beam quality of PFF-SBC at a current of 1.6 A. (b) Beam quality of single PTLD at a current of 1.6 A.