Laser Transmission Studies with Magnetic Nanofluids

TL;DR

This study investigates how magnetic nanofluids alter laser transmission and scattering under magnetic fields, revealing non-linear and magneto-optical effects useful for developing advanced optofluidic devices.

Contribution

It provides new insights into the non-linear optical behavior and scattering patterns of magnetic nanofluids under magnetic fields, aiding in optofluidic device development.

Findings

Magnetic field influences forward scattered laser patterns.

Change in non-linear refractive index observed.

Spatial and temporal evolution of scattering patterns characterized.

Abstract

Transmission of He-Ne (632 nm, 10 mW) Gaussian laser beam through Hexane and Water based magnetic nanofluids containing Fe3O4 nanoparticles show strong non-linear and magneto-optical effects. Application of external magnetic field (up to 1.7 Wb/m2) perpendicular to the incident laser beam produces a change in forward scattered pattern of the incident laser beam. Dependence of forward scattered patterns in presence of external magnetic field has been studied. Image processing has been carried out to understand spatial distribution of the forward scattered patterns and temporal evolution of patterns involving particle image velocimetry technique. Change in non-linear refractive index is estimated for samples showing self-diffraction arising from higher order non-linear optical effect. Observed effects are useful for understanding light scattering from magnetic nanofluids and developing optofluidic devices and sensors.