Near-infrared surface plasmon polariton dispersion control with hyperbolic metamaterials

Abstract

We demonstrate experimentally signatures and dispersion control of surface plasmon polaritons from 1 to 1.8 µm using periodic multilayer metallo-dielectric hyperbolic metamaterials. The fabricated structures are comprised of smooth films with very low metal filling factor. The measured dispersion properties of these hyperbolic metamaterials agree well with calculations using transfer matrix, finite-difference time-domain, and effective medium approximation methods despite using only 2.5 periods. The enhancement factor in the local photonic density of states from the studied samples in the near-infrared wavelength region is determined to be 2.5-3.5. Development of this type of metamaterial is relevant to sub-wavelength imaging, spontaneous emission and thermophotovoltaic applications.

From surface to volume plasmons in hyperbolic metamaterials: General existence conditions for bulk high-kwaves in metal-dielectric and graphene-dielectric multilayers

“…Hyperbolic dispersion was demonstrated experimentally [8], as was an anomalous increase of the decay rate of nearby emitting centers (a broadband Purcell effect) [1,6], along with the direct measurement of radiation enhancement [9]. Many applications of HMMs have been suggested, such as far-field subwavelength imaging or "hyperlensing" [3] and highly absorptive surfaces that benefit (rather than suffer) from increased roughness [7,10], including nanoparticle-induced [11] and internal layer [12] roughness.…”

Nano Sensing and Energy Conversion Using Surface Plasmon Resonance (SPR)

“…Unresolved issues in the optical characterization of nanofluids are the effective refractive index at high concentrations [4] and the change of optical property during the solidification of nanofluids [3]. The approach of higher refractive index prism, tunable SPR resonance wavelength, and enhanced sensitivity is expected to address these issues [18,19,20]. …”

“…Spoof surface plasmon resonance, based on HMM, demonstrates effective SPR dispersion or wavelength control and exotic optical properties, which can be combined with SPR imaging for the selection of the SPR wavelength, depending on samples, providing higher sensitivity and enhanced spatial resolution. Figure 5a,b show a schematic and SEM image of hyperbolic metamaterials (HMM) comprised of smooth films (Au metal and SiO 2 dielectric) with a very low metal filling factor [20]. HMM is fabricated by the e-beam evaporation technique.…”

“…The free space light line is indicated by a light dotted line. The inset table summarizes the experimentally obtained shortest SPP wavelengths for the three samples [20]. …”

“…This technique can be more powerful if its sensitivity can be increased in order to monitor the fine ion change in bio applications through grating structure [18] and high refractive index sheets [19]. Another idea is to combine the exotic optical properties of hyperbolic metamaterials (HMM) with its SPR resonance dispersion controllability to improve sensitivity [20]. …”