Magneto-optic surface plasmon resonance properties of core-shell Fe₃O₄@Ag nanoparticles

Abstract

The magneto-optic surface plasmon resonance (MOSPR) properties of core-shell Fe3O4@Ag nanoparticles (NPs) were successfully investigated using the Kretschmann configuration. The four layer configuration system consists of prism/Au/Fe3O4@Ag/air. At the plasmon resonance frequency, a prominent resonant enhancement of magneto-optical activity was observed. An external magnetic field of 40, 50 and 60 Oe was applied in the longitudinal, polar, and transversal configurations with variation in the positive and negative directions in the longitudinal configuration. In the longitudinal configuration, the SPR angle shifted to the larger and lower angles when an external magnetic field was applied in the positive and negative directions, respectively. Under an external magnetic field, the SPR angle shifted to the larger angle for polar and transversal configurations. The non-reciprocal reflection of light was exploited under an external magnetic field applied to core-shell Fe3O4@Ag magnetic NPs. The SPR angle shift is observed in each configuration. The results indicated that the MOSPR system might be used for next generation of biosensor application.

Green Synthesis of Fe3O4/Chitosan Nanoparticles Utilizing Moringa Oleifera Extracts and Their Surface Plasmon Resonance Properties

“…The SPR properties of the samples were examined using our laboratory's hand-made SPR spectroscopy system based on previous publications. 50,51,57,58 The Kretschmann configuration was chosen to attain the resonant condition (the reflected light intensity decreases sharply). 4,59 The experimental setup for measuring the SPR properties consists of the following parts: optical and mechanical instruments, the main unit, and a computer, as shown in Fig.…”

“…The SPR spectra output (reflected light versus the angle of the incident light) was displayed by a computer, and then analyzed by observers. 32,57,60,61 SPR spectra result from plasmon excitation by an evanescent wave incident at a particular angle was greater than the critical angle. An evanescent wave is formed when a propagating laser beam in the prism encounters the metal-dielectric interface.…”

Fe3O4/CoFe2O4 core-shell nanoparticles with enhanced magnetic properties for hyperthermia application

“…Besides, magnetic nanoparticles have been detected in liver, spleen, kidney and other organs in the body after hyperthermia treatment [10]. Therefore, in biomedical applications, the nanoparticles must meet several requirements including low concentration, effective magnetic induction heating capacity and biocompatibility [11][12][13][14][15]. Among magnetic nanoparticles, Fe 3 O 4 nanoparticles have acquired much interest in biomedical applications owing to their biocompatibility and high magnetisation (90 emu g −1 at room temperature) [16].…”

Ferromagnetic Subwavelength Periodic Nanogroove Structure with High Magneto-Optical Kerr Effect for Sensing Applications

“…The magneto-optical Kerr effect (MOKE) can display diverse responses concerning the direction of the magnetization, incident plane, and sample surface, and it mainly occurs in three different forms: longitudinal MOKE, polar MOKE with respect to the change in light polarization, and transverse MOKE (TMOKE), which evaluates the intensity change of the light in the reflected or transmitted directions. − Magneto-optical devices based on TMOKE have attracted considerable attention and have driven the advancement in the sensing of biomolecules, gases, , water, − butanol, and chloroform . The primary requirement for these applications is that the device must exhibit a detectable TMOKE signal.…”

“…In recent years, attempts to design efficient magnetoplasmonic devices have encountered three challenges which are low magnitude with sensing performance, incompatibility with the microfluidic platform, and the complex fabrication process. Conventionally, the magnitude and sensing performance of TMOKE were increased by building a multilayer system comprising noble metals and magnetic materials assisted by a large-volume prism. ,, For instance, Qin and Bi and Ayareh et al designed the structures TiN/SiO 2 /YIG/CeYIG/Au and glass/Au/Co/Au/glucose, respectively, which contain noble metal and ferromagnetic layers and used a large visible prism system to excite the SPR mode. This approach enabled them to generate a high-intensity sharp TMOKE signal in the resonance region, which improved the response to the change in the refractive index and figure of merit (FoM) for the detection of small molecules at ultra-low concentrations.…”