We describe methods of Raman spectroscopy for resolving mono crystalline sucrose using vortex laser beam modes with circular polarization. Research up to this point has led to controversy as to whether beams carrying orbital angular momentum (OAM) are capable of interacting with chiral matter, but there is also a general lack of experimental or theoretical research into the interaction of vortex beams carrying OAM or vector beams with vibrational modes in matter. Our attempts to detect and measure interactions with sucrose in crystal form mediated by OAM have resulted in findings that indicate a worthy path for future inquiry.
Light scattering and transmission of optical Laguerre Gaussian (LG) vortex beams with different
orbital angular momentum (OAM) states in turbid scattering media were investigated in
comparison with Gaussian (G) beam. The scattering media used in the experiments consist of
various sizes and concentrations of latex beads in water solutions. The LG beams were generated
using a spatial light modulator in reflection mode. The ballistic transmissions of LG and G
beams were measured with different ratios of thickness of samples (z) to scattering mean free
path (ls) of the turbid media, z/ls. The results show that in the ballistic region where z/ls is small,
the LG and G beams show no significant difference, while in the diffusive region where z/ls is
large, LG beams show higher transmission than Gaussian beam. In the diffusive region, the LG
beams with higher orbital angular momentum L values show higher transmission than the beams
with lower L values. The transition points from ballistic to diffusive regions for different
scattering media were studied and determined.