Fig. 1. Yellow laser output by pumping Dy-Tb∶LiLuF₄ crystal with single laser diode. (a) Schematic of experimental setup; (b) continuous wave (CW) output power versus absorbed pump power with the corresponding laser spectrum in inset

Fig. 2. Yellow laser output by pumping Dy-Tb∶LiLuF₄ crystal with double laser diodes with polarization beam coupling. (a) Schematic of experimental setup; (b) CW output power versus absorbed pump power

Fig. 3. Characterization of black phosphorus. (a) Raman spectrum of black phosphorus; (b) transmission spectrum of black phosphorus and sapphire substrate. Inset: the black phosphorus sample photograph

Fig. 4. Measurement and characterization of nonlinear saturable absorption properties of black phosphorus. (a) Schematic of experimental setup; (b) transmissivity of black phosphorus versus input pulse peak power

Fig. 5. Experimental results of black phosphorus passively Q-switched yellow laser. (a) Average output power versus absorbed pump power; (b) repetition rate and pulse width versus absorbed pump power; (c) pulse sequence under the repetition rate of 10 kHz; (d) minimum single pulse during the experiment