Dual-Wavelength Nanosecond Nd:YVO4 Laser With Switchable Inhomogeneous Polarization Output

We report a compact dual-wavelength nanosecond Nd:YVO
₄
laser with switchable radially and azimuthally polarized output. The single-wavelength (1064.66 nm) or dual-wavelength (1064.50 and 1064. 66 nm) operation can be delivered and switched by adjusting the intracavity birefringent filter. In addition, the switchable radially and azimuthally polarized beams could be obtained in the continuous-wave (CW) and actively Q-switched operation via the intracavity polarization manipulation. In the CW operation regime, the slope efficiency of single- and dual-wavelength laser could reach up to 11.3% and 25.5%, respectively. For the actively Q-switched operation, the single-wavelength laser can deliver pulse with the shortest duration 30 ns and the peak power 0.65 kW, and the dual-wavelength laser can deliver the pulse with the shortest pulse duration 28 ns and the peak power 0.83 kW. This multifunctional laser could enrich the manipulation potential of the solid-state laser, and would benefit lots of applications, such as THz wave generation, materials processing, fiber, and free space communication.