Dual-cavity dual-frequency laser based on twisted-mode cavity structure

To achieve orthogonally linearly polarized single-longitudinal-mode dual-frequency laser output and suppress spatial hole-burning effects, a dual-cavity dual-frequency Nd:YAG laser system was designed based on a twisted-mode cavity configuration. The working principle of the twisted-mode cavity laser was analyzed theoretically, and the energy distribution of the standing wave field was obtained. A two-cavity dual-frequency Nd:YAG laser based on twisted-mode cavity was designed. The polarization splitting prism was used as the polarization element to enable the two standing wave cavities to operate in a single longitudinal mode oscillation. The orthogonal linear polarization 1 064 nm dual-frequency laser output was obtained, which means that the spatial hole burning effect was effectively suppressed. Experimental results demonstrate that at a pump power of 2 W, the straight sub-cavity delivers an output power of 5.76 mW, while the L-shaped sub-cavity produces 1.97 mW. Both sub-cavities achieve orthogonally linearly polarized single-longitudinal-mode laser outputs at 1 064 nm, effectively suppressing spatial hole-burning effects. These findings conclusively validate that the twisted-mode cavity configuration exhibits remarkable advantages in enabling coaxial dual-frequency laser output.