Laguerre–Gaussian beam scattering by a marine aerosol

Abstract

Generalized Lorenz–Mie theory (GLMT) is extensively utilized in the modelling and characterization of optical wave interaction with environmental aerosols. More specifically, the scattering of a Laguerre–Gaussian (LG) beam from a spherical marine aerosol particle is analyzed using the GLMT. By employing the GLMT and complex source point method, the scattering field coefficients of LG beams illuminating a marine aerosol particle are determined by implementing the boundary conditions on the surface of the marine aerosol. As compared to plane waves or Gaussian beams (GBs), the optical fields of LG beams are more tangled so their interaction with the target (i.e., marine aerosol particle) is also different. To detect change in the relative humidity $({H}_{r})$ of the marine aerosol, the LG beams are more effective. Influences of various parameters (i.e., radial mode $\left(p\right)$, azimuthal mode $\left(l\right)$, beam waist radius $\left({w}_{0}\right)$, beam wavelength $(\lambda )$, beam center locations $({x}_{0}, {y}_{0}, {z}_{0})$, and relative humidity $({H}_{r})$) on the differential scattering cross-section (DSCS) in far-field scattering are investigated. Thus, the DSCS caused by the marine aerosol particle can be tuned by selecting suitable parameters among those mentioned above. This research work can also help to elucidate the interaction between LG beams and spherical marine aerosol particles with layer structures.