Fig. 1. Cavity structure diagram of pulsed LD end pumped Tm:YAG laser

Fig. 2. Structure schematic diagram of square Tm:YAG crystal model and heat sink experimental device . (a) Heat sink experimental device; (b) Single-ended bonded crystal model; (c) Double-ended bonded crystals

Fig. 3. Three-dimensional temperature distribution of square composite Tm:YAG crystal. (a) Longitudinal section of single-ended bonded crystal (y=0); (b) single-ended bonded gain crystal end face (z=c₁); (c) Longitudinal section of double-ended bonded crystal (y=0); (d) Double-ended bonded gain crystal end face (z=c₁)

Fig. 4. Temperature profile of single-ended bonded crystal (x=0). (a) $$\text{Unknown environment 'document'}$$=0 mm; (b) $$\text{Unknown environment 'document'}$$=0.2 mm; (c) $$\text{Unknown environment 'document'}$$=0.4 mm; (d) $$\text{Unknown environment 'document'}$$=0.6 mm

Fig. 5. Temperature profile of double-ended bonded crystal (y=0). (a) c₁=0.2 mm; (b) c₁=0.4 mm; (c) c₁=0.6 mm

Fig. 6. The maximum temperature in the composite crystal varies with the thickness of the gain crystal

Fig. 7. Stress distribution of YAG/Tm:YAG crystals. (a) Single-ended bonding; (b) Double-ended bonding

Fig. 8. YAG/Tm:YAG crystal side profile stress distribution(x=0). (a) Single-ended bonding; (b) Double-ended bonding

Fig. 9. Three-dimensional distribution of thermal deformation of composite crystal (y=0). (a) Single-ended bonding; (b) Double-ended bonding

Fig. 10. Profile profile variable distribution of single-ended bonded Tm:YAG composite crystal (y=0). (a) $$\text{Unknown environment 'document'}$$=0 mm；(b) $$\text{Unknown environment 'document'}$$=0.2 mm；(c) $$\text{Unknown environment 'document'}$$=0.4 mm；(d) c₁=0.6 mm

Fig. 11. Double-ended bond Tm:YAG composite crystal profile profile variable distribution (x=0). (a) c₁=0.4 mm; (b) c₁=0.8 mm; (c) c₁=1.2 mm

Table 1. Thermal performance of Tm:YAG crystal^[16]