Fig. 1. Phase matching curves of BGSe at room temperature under (a) type I and (b) type II-B conditions (${\lambda }_3=1064\mathrm{nm}$).

Fig. 2. Phase matching curve at 20°C, 80°C, and 140°C under (a) type I and (b) type II-B conditions (${\lambda }_3=1064\mathrm{nm}$, $\varnothing =0°,20°$).

Fig. 3. Wavelength of idler light at T$=20°\mathrm{C}$ and $\mathrm{\Delta }{\lambda }_2/\mathrm{\Delta }$T at each $\theta$ when $\varnothing =0°$ under (a) type I and (b) type II-B conditions.

Fig. 4. Schematic diagram of the experimental setup.

Fig. 5. Output at 3611–3619 nm of BGSe (56.3°, 0°).

Fig. 6. Idler light’s peak wavelength of BGSe (56.3°, 0°) at 30°C–140°C.