Fig. 1. Schematic diagram of THG based on mixing broadband and narrowband

Fig. 2. Numerical model of super-luminescent light. (a) Time domain spectrum; (b) frequency domain spectrum

Fig. 3. Efficiency and spectra of harmonic generation. (a) Influence of crystal length on SHG efficiency curve; (b) influence of crystal length on THG efficiency curve; (c) spectrum of each wave in frequency conversion

Fig. 4. THG results of mixing broadband and narrowband and direct THG. (a) Efficiency curves; (b) spectrum of mixing broadband SHG (3 THz) and narrowband FW; (c) spectrum of direct THG

Fig. 5. Results of different bandwidth of mixing broadband SHG and narrowband FW. (a) Efficiency curve; (b) spectrum of mixing broadband SHG (2 THz) and narrowband FW; (c) spectrum of mixing broadband SHG (1 THz) and narrowband FW

Fig. 6. Results of mixing narrowband FW and broadband SHG. (a) Efficiency curve; (b) spectrum of mixing narrowband SHG and broadband FW (3 THz)