Fig. 1. Structural diagram of standing wave cavity SRO

Fig. 2. Structural diagram of ring cavity SRO

Fig. 3. Stability parameter of SRO cavity versus resonator cavity length

Fig. 4. Stability parameter of SRO cavity versus thermal focal length of MgO∶PPLN crystal

Fig. 5. Experimental setup for generating continuous-wave single-frequency infrared laser by SRO

Fig. 6. Output power of signal and idler light from SRO versus pump power (point is experimental data and curve is theoretical prediction result)

Fig. 7. Power of signal and idler light versus time when SRO is free running. (a) Standing wave cavity SRO; (b) ring cavity SRO

Fig. 8. Frequency drift curve of signal light when SRO is free running. (a) Standing wave cavity SRO; (b) ring cavity SRO

Fig. 9. Output power of signal and idler light and frequency of signal light versus time when ring cavity SRO is free running. (a) Power of signal and idler light versus time; (b) frequency of signal light versus time