OAM transmission of polarized multipole laser beams in rat cerebellum tissue

This paper focuses on the study of the transmission of the cerebellum tissue at different oxygen levels and the interaction with multipoles of well-defined polarized orbital angular momentum (OAM) beams, known as optical vortices. The optical vortices interacting with the cerebellum tissue play a key role in our research. The electric field of these OAM beams can be expanded in terms of multipoles of Laguerre–Gaussian​ modes, which can interact favorably with the multipoles properties of the media as the light propagates. This interaction is best when the multipoles of both the beam and the media match as Eigen states A light beam carrying polarization or OAM has shown to be of importance when propagating through a scattering media. Additionally, the cerebellum is a unique and crucial part of the brain; here it is studied at two different oxygen levels—control (21% oxygen) and hypoxia (7% oxygen). The transmittance of different light states (OAM and polarization) is measured and analyzed for both. Our results indicate that the control sample presents a higher transmission and polarization dependency for right circular polarization as for this polarization state the overall transmission increases from 2.85% to 6.65%. This transmission percentage is followed by a Majorana vector beam (with vertical input polarization) as its transmission increases from 2.8% to 5.9%. In general the studied transmission increases with respect to the OAM value from L=0 to 3. These observations are attributed to the structure and topology of the multipoles of a given beam when interacting with a bio-media and the matching up of their respective multipole moment distribution.