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

Abstract

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.