Topological Insulator Simultaneously Q-Switched Dual-Wavelength $\hbox {Nd}:\hbox {Lu}_{2}\hbox {O}_{3}$ Laser

We demonstrated the dual-wavelength simultaneously Q-switched Nd: Lu₂O₃ laser with a topological insulator Bi₂Se₃ as the Q-switcher. The continuous-wave Nd:Lu₂O₃ crystal laser with the slope efficiency of 31% was achieved, and the first Nd:Lu₂O₃ pulsed laser operation was reported, as far as we know. By using the wavelength-insensitive saturable absorption of topological insulators, the dual wavelength of the Nd:Lu₂O₃ crystal laser can be Q-switched simultaneously without the frequency selection of the saturable absorber, since the emission cross-sections of Nd:Lu₂O₃ at the wavelengths of 1077 and 1081 nm are comparable. The results indicate that the topological insulator is wavelength-insensitive and should be suitable for the dual-wavelength simultaneously Q-switched laser as a passive Q-switcher. It can be proposed that this work would provide an efficient technology for the dual-wavelength simultaneously Q-switched laser, which has promising applications in many regimes.