Characterisation and Manipulation of Polarisation Response in Plasmonic and Magneto-Plasmonic Nanostructures and Metamaterials

Abstract

Optical properties of metal nanostructures, governed by the so-called localised surface plasmon resonance (LSPR) effects, have invoked intensive investigations in recent times owing to their fundamental nature and potential applications. LSPR scattering from metal nanostructures is expected to show the symmetry of the oscillation mode and the particle shape. Therefore, information on the polarisation properties of the LSPR scattering is crucial for identifying different oscillation modes within one particle and to distinguish differently shaped particles within one sample. On the contrary, the polarisation state of light itself can be arbitrarily manipulated by the inverse designed sample, known as metamaterials. Apart from polarisation state, external stimulus, e.g., magnetic field also controls the LSPR scattering from plasmonic nanostructures, giving rise to a new field of magneto-plasmonics. In this review, we pay special attention to polarisation and its effect in three contrasting aspects. First, tailoring between LSPR scattering and symmetry of plasmonic nanostructures, secondly, manipulating polarisation state through metamaterials and lastly, polarisation modulation in magneto-plasmonics. Finally, we will review recent progress in applications of plasmonic and magneto-plasmonic nanostructures and metamaterials in various fields.

Circular Polarization Conversion in Single Plasmonic Spherical Particles

“… 9 , 10 Apart from that, plasmonic materials are also designed and fabricated as metamaterials to control or convert the polarization of light, for example, by rotating the plane of polarization of linearly polarized light or by changing ellipticity and handedness. 11 − 13 …”

“…Plasmons can be accompanied by a substantial enhancement of the local electric field leading to surface-enhanced Raman scattering and fluorescence . Plasmons can also undergo spectral shift and broadening upon molecule adsorption and reconfiguration by chemical and refractive index damping. , Damping of plasmons leads to a series of applications such as molecule sensors, ,− hot-electron transfer-induced photocatalysis, photovoltaics, and can facilitate subwavelength confinement and propagation in microstructures in photonics. , Apart from that, plasmonic materials are also designed and fabricated as metamaterials to control or convert the polarization of light, for example, by rotating the plane of polarization of linearly polarized light or by changing ellipticity and handedness. − …”

Modeling of Enhanced Polar Magneto-Optic Kerr Effect by Surface Plasmons in Au Bowtie Arrays

“…Therefore, improving the observation accuracy of magneto-optical Kerr is still an important issue [ 10 ]. Magneto-optic surface plasmon resonance (MOSPR) can be controlled by external magnetic fields, overcoming this limitation [ 11 , 12 ]. Early MOSPR investigations concentrated on a few flat, pure ferromagnetic films, and to improve the MO effects, surface plasmon resonance (SPR) was activated on the surface of these films [ 13 , 14 , 15 ].…”

Surface Plasmon Photodetectors Based on Noble Metals

“…Plasmonic materials, when properly illuminated with visible or near infrared wavelengths, exhibit unique and interesting characteristics that can be exploited to tailor and adjust the radiation and propagation properties of light to nanoscale dimensions [1][2][3][4][5][6][7][8]. Various plasmonic structures have been exploited for optical signal filtering [9,10], switches [11,12], transport [13,14], modulation [15,16] and detection [17,18].…”