Fig. 1. Schematic of the 275 nm laser

Fig. 2. The energy level and room temperature polarization-dependent emission Pr:YLF cross-sections

Fig. 3. Pr:YLF fluorescence spectrum from 500 nm to 570 nm

Fig. 4. Focusing shape and size of pump beam spot with a fast-axis collimating blue diode

Fig. 5. M₂ coating curve (short-wave-pass)

Fig. 6. M₃ coating curve (long-wave-pass)

Fig. 7. The output power of 275 nm versus the incident pump power

Fig. 8. 275 nm laser spectrum

Fig. 9. The beam spot and M-square of the 275 nm laser

Fig. 10. 275 nm laser power stability