  The past decade has seen tremendous progress in the production and
utilization of vortex and vector laser pulses. Although both are considered as
structured light beams, the vortex lasers have helical phase fronts and phase
singularities, while the vector lasers have spatially variable polarization
states and polarization singularities. In contrast to the vortex pulses that
carry orbital angular momentum (OAM), the vector laser pulses have a complex
spin angular momentum (SAM) and OAM coupling. Despite many potential
applications enabled by such pulses, the generation of high-power/-intensity
vortex and vector beams remains challenging. Here, we demonstrate using theory
and three-dimensional simulations that the strongly-coupled stimulated
Brillouin scattering (SC-SBS) process in plasmas can be used as a promising
amplification technique with up to 65% energy transfer efficiency from the pump
beam to the seed beam for both vortex and vector pulses. We also show that
SC-SBS is strongly polarization-dependent in plasmas, enabling an all-optical
polarization control of the amplified seed beam. Additionally, the interaction
of such structured lasers with plasmas leads to various angular momentum
couplings and decouplings that produce intense new light structures with
controllable OAM and SAM. This scheme paves the way for novel optical devices
such as plasma-based amplifiers and light field manipulators.
