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Magnetoplasmonic properties of perpendicularly magnetized $[$Co/Pt$]_{N}$ nanodots

Optics 2020-02-19 v1 Materials Science

Abstract

We demonstrate a ten-fold resonant enhancement of magneto-optical effects in perpendicularly magnetized [[Co/Pt]N]_{N} nanodots mediated by the excitation of optimized plasmon modes. Two magnetoplasmonic systems are considered; square arrays of [[Co/Pt]N]_{N} nanodots on glass and identical arrays on a Au/SiO2 bilayer. On glass, the optical and magneto-optical spectra of the nanodot arrays are dominated by the excitation of a surface lattice resonance (SLR), whereas on Au/SiO2{}_{2}, a narrow surface plasmon polariton (SPP) resonance tailors the spectra further. Both the SLR and SPP modes are magneto-optically active leading to an enhancement of the Kerr angle. We detail the dependence of optical and magneto-optical spectra on the number of Co/Pt bilayer repetitions, the nanodot diameter, and the array period, offering design rules on how to maximize and spectrally tune the magneto-optical response of perpendicularly magnetized [[Co/Pt]N]_{N} nanodots.

Keywords

Cite

@article{arxiv.1911.06535,
  title  = {Magnetoplasmonic properties of perpendicularly magnetized $[$Co/Pt$]_{N}$ nanodots},
  author = {Francisco Freire-Fernández and Rhodri Mansell and Sebastiaan van Dijken},
  journal= {arXiv preprint arXiv:1911.06535},
  year   = {2020}
}