Cascaded vector vortex mode generation from a solid-state Raman laser.

Cascaded vector vortex mode generation from a Ba(NO3)2 Raman laser cavity pumped by a vector LG0,2 green laser was demonstrated for the first time to our knowledge. The generated Stokes outputs exhibited a second-order vector vortex beam as evidenced by linearly polarized flower-shaped spatial forms with four petals. The achieved optical conversion efficiencies of the first, second, and third Stokes outputs were 6.59%, 4.22%, and 0.11%, respectively, at a maximum pump energy of 3.6 mJ (360 mW).