Abstract
The optical and magneto-optical (MO) properties of composites containing magnetic nanoparticles were experimentally as well as theoretically found to be dependent on the interparticle spacing, surrounding medium and particle size of the constituent nanoparticles. In this work, the optical and MO properties of composites consisting of two nickel (Ni) nanoparticles (NP) and embedded in polymethyl methacrylate were theoretically investigated in the wavelength range of 400–900 nm using the discrete dipole approximation method, which accounts for optical coupling between Ni NPs. The theoretical calculations suggest that the shifts in spectral peak position depend on both interparticle distance and particle size corresponding to the experimental results. In addition, the observed optical spectra of Ni NPs showed the plasmon resonance in the visible light range in the electromagnetic wave. The basic results of this study might be used for fabricating optical and MO devices.
Acknowledgements
This work was financially supported by the Division of Research Administration, Research and Technology Transfer Affairs, Khon Kaen University (Grant Year 2018) and acknowledge all facilities and support from the Faculty of Applied Science and Engineering, Nong Khai Campus, Khon Kaen University. The authors also extend thanks to Dr. Kataja Veli for advice about the dielectric constant of nickel.