Fig. 1. (a) Schematic diagram illustrating the working principle of the spectral programmable MIR OPO. NIR, near-infrared; MIR, mid-infrared. (b) Schematic experimental setup of the spectral programmable MIR OPO. LD, laser diode; PM YDF, polarization-maintaining Yb-doped fiber; AOTF, acousto-optical tunable filter; RF, radio frequency; SPFL, spectral programmable fiber laser; MgO:PPLN, MgO-doped periodically poled lithium niobate; OSA, optical spectrum analyzer; PM, power meter.

Fig. 2. (a) Central wavelength tunable idler spectra and (b) corresponding pump spectra. (c) Simulated (lines) and measured (dots) parametric wavelengths with the corresponding pump wavelengths. (d) Idler power as a function of the pump power.

Fig. 3. (a) Interval tunable dual-wavelength idler spectra and (b) corresponding interval tunable dual-wavelength pump spectra.

Fig. 4. Intensity tunable idler spectra with (a) 33% idler at 3283 nm and 67% idler at 3028 nm, (b) 91% idler at 3028 nm and 9% idler at 3283 nm, (c) 67% idler at 3283 nm and 33% idler at 3028 nm, and (d) 9% idler at 3028 nm and 91% idler at 3283 nm. Corresponding pump spectra with (e) 52% pump wave at 1050 nm and 48% pump wave at 1070 nm, (f) 55% pump wave at 1050 nm and 45% pump wave at 1070 nm, (g) 45% pump wave at 1050 nm and 55% pump wave at 1070 nm, and (h) 34% pump wave at 1050 nm and 66% pump wave at 1070 nm.

Fig. 5. (a) Triple-wavelength idler spectrum at 3071 nm, 3166 nm, and 3257 nm, and its corresponding (b) triple-wavelength pump spectrum at 1053 nm, 1060 nm, and 1068 nm.

Fig. 6. Triple-wavelength custom-tailored idler spectra with (a) downhill shape, (b) basin shape, (c) uphill shape, and (d) peak shape. Corresponding pump spectra with (e) downhill shape, (f) basin shape, (g) uphill shape, and (h) peak shape.

Fig. 7. (a) Broadband idler spectra with 10 dB bandwidth of 20 nm, 50 nm, 65 nm, 95 nm, and 125 nm. (b) Corresponding broadband pump spectra with 10 dB bandwidth of 3 nm, 7 nm, 10 nm, 12 nm, and 14 nm. (c) Simulated and measured broadband signal spectrum. (d) Simulated and measured broadband idler spectrum.

Fig. 8. (a) Tunable signal spectra. (b) Spectral evolution during power scaling at 3028 nm. (c) Pump-to-idler conversion efficiency at different idler wavelengths.

Fig. 9. (a) PER and 3 dB linewidth dependence on pump wavelength. (b) Power stability of the 3028 nm idler within 6 min.

Fig. 10. (a) Dual-wavelength interval tunable signal spectra. (b)–(e) Dual-wavelength amplitude tunable signal spectra. (f)–(i) Triple-wavelength intensity envelope tunable signal spectra.

Fig. 11. (a) Simulated dual-wavelength interval tunable parametric gain spectrum (solid lines) and the measured central wavelength position (dashed lines). (b)–(e) Simulated dual-wavelength intensity tunable parametric gain spectrum (solid lines) and the measured intensity level (dashed lines). (f)–(i) Simulated triple-wavelength intensity envelope tunable parametric gain spectrum (solid lines) and the measured envelope shape (dashed lines).

Fig. 12. (a) Triple-wavelength idler spectral stability over 7 min. (b) Triple-wavelength total idler power stability.