Fig. 1. Collinear phase matching in negative uniaxial crystal

Fig. 2. Phase-matching curves in various deuteration level

Fig. 3. Variation relationships between parametric bandwidths、walk-off angles and deuterium doping level

Fig. 4. Numerical simulation temporal characteristics of OPA processes

Fig. 5. Simulation temporal characteristics of OPA processes under different pump intensities

Fig. 6. Experimental layout

Fig. 7. Signal characteristics of OPA processes

Fig. 8. Variation of signal magnification with external angle

Fig. 9. Spectral gain at different external angles

Fig. 10. Variation of signal intensity after OPA with pump intensity under different initial signal intensity