Hybrid plasmonic lattices with tunable magneto-optical activity

Abstract

We report on the optical and magneto-optical response of hybrid plasmonic lattices that consist of pure nickel and gold nanoparticles in a checkerboard arrangement. Diffractive far-field coupling between the individual emitters of the lattices results in the excitation of two orthogonal surface lattice resonance modes. Local analyses of the radiation fields indicate that both the nickel and gold nanoparticles contribute to these collective resonances and, thereby, to the magneto-optical activity of the hybrid arrays. The strong effect of noble metal nanoparticles on the magneto-optical response of hybrid lattices opens up new avenues for the realization of sensitive and tunable magneto-plasmonic nanostructures.

Hybrid Ni/SiO2/Au dimer arrays for high-resolution refractive index sensing

“…Recently, the excitation of SLRs in arrays of ferromagnetic nickel nanoparticles was demonstrated [22]. The magneto-optical activity of an ordered ferromagnetic array is larger than that of randomly distributed nanoparticles, and it tunes sensitively with the period and symmetry of the lattice [22][23][24] or the size or shape of the nanoparticles [25]. The ability to compensate for intrinsic damping via the excitation of SLR modes offers new perspectives for refractive index sensing based on magnetoplasmonic architectures.…”

“…In all these realizations, the magnetic constituent is in direct contact with the noble metal. Dimer nanodisks wherein a dielectric layer separates the ferromagnet and noble metal [31,35,36] and composite arrays of pure ferromagnetic and noble metal nanoparticles [24] have also been explored.…”

Plasmonic nanodevice with magnetic funcionalities: fabrication and characterization

“…Hence, it is difficult to achieve ferromagnetic and plasmonic behaviors in the same material. Only recently, nanostructures of Ni [14][15][16][17][18][19][20] Ni/Co [21] and permalloy antidots [22] have been reported to exhibit surface plasmons in combination with their well-known ferromagnetic character at room temperature. However, the intensity of the plasmonic resonance in these type of materials is fairly weaker than for noble metals as Au or Ag where the electromagnetic field can be increased locally up to 80 times upon excitation of surface plasmons [23].…”

Surface-plasmon-polariton-driven narrow-linewidth magneto-optics in Ni nanodisk arrays

“…Another loss reduction strategy in magnetoplasmonics involves the integration of noble and magnetic metals. Realizations such as near-field coupled vertical dimers [21][22][23] and far-field coupled checkerboard patterns [24] have shown a moderate narrowing of plasmon resonances compared to the all-magnetic structures. The loss properties of these hybrid magnetoplasmonic systems can be understood by considering the coupling of weakly and heavily damped oscillators that are driven near their resonance frequencies by an external force.…”