Nonlinear and magneto-optical transmission studies on magnetic nanofluids of non-interacting metallic nickel nanoparticles

Abstract

Oxide free stable metallic nanofluids have the potential for various applications such as in thermal management and inkjet printing apart from being a candidate system for fundamental studies. A stable suspension of nickel nanoparticles of ∼ 5 nm size has been realized by a modified two-step synthesis route. Structural characterization by x-ray diffraction and transmission electron microscopy shows that the nanoparticles are metallic and are phase pure. The nanoparticles exhibited superparamagnetic properties. The magneto-optical transmission properties of the nickel nanofluid (Ni-F) were investigated by linear optical dichroism measurements. The magnetic field dependent light transmission studies exhibited a polarization dependent optical absorption, known as optical dichroism, indicating that the nanoparticles suspended in the fluid are non-interacting and superparamagnetic in nature. The nonlinear optical limiting properties of Ni-F under high input optical fluence were then analyzed by an open aperture z-scan technique. The Ni-F exhibits a saturable absorption at moderate laser intensities while effective two-photon absorption is evident at higher intensities. The Ni-F appears to be a unique material for various optical devices such as field modulated gratings and optical switches which can be controlled by an external magnetic field.

Preparation, optical and non-linear optical power limiting properties of Cu, CuNi nanowires

“…From the reported values (Refs. [21][22][23][24][25][26], the values of b are lower than our b values where as their reported I s are higher when compared with our values. The higher values of I s observed in the ZnO-GO hybrid system 26 which may be due to two photon absorption (TPA) with reverse saturable absorption and photo-induced photon transfer between ZnO and graphene sheets and direct comparison could not be made with other reported values.…”

Passively Q-switched erbium-doped fiber laser using Fe3O4-nanoparticle saturable absorber

“…If the pump power is reduced to 110 mW again, the Q-switching reappeared. This is because FONP exhibits a saturable absorption at moderate laser intensities, while optical limiting induced by excited states absorption would occur at higher intensities [23,28,32].…”

“…This is because FONPs exhibit a saturable absorption at moderate intensity, but optical limiting induced by excited-state absorption would occur at higher intensity. 25,30,33) To verify the effects of the FONP-based SA on Qswitching, two optical fiber pigtails connected by a flange without FONPs are inserted in the EDFL cavity. The lengths of the corresponding SMFs are not changed.…”

Magneto-Plasmonic Colloidal Nanoparticles Obtained by Laser Ablation of Nickel and Silver Targets in Water

“…Due to the nature of transition metals, nanosized nickel has found applications in the fields of magnetic devices, , catalysts, , batteries, fuel cells, , and solar cells, among others. Hence, the synthesis of Ni nanoparticles has attracted considerable attention.…”