Interferometric characterization of a sub-wavelength near-infrared negative index metamaterial

Abstract

Negative phase advance through a single layer of near-IR negative index metamaterial (NIM) is identified through interferometric measurements. The NIM unit cell, sub-wavelength in both the lateral and light propagation directions, is comprised of a pair of Au strips separated by two dielectric and one Au film. Numerical simulations show that the negative phase advance through the single-layer sample is consistent with the negative index exhibited by a bulk material comprised of multiple layers of the same structure. We also numerically demonstrate that the negative index band persists in the lossless limit.

Polarization interferometry for real-time spectroscopic plasmonic sensing

“…Experimental data collected with LabVIEW software was analyzed within a MATLAB script using the following equations 11 :…”

“…[1][2][3][4][5][6][7][8] While many geometries, devices, and illumination methods have been used, typical SPR sensing measurements yield only intensity information in the form of a reflection, transmission, or scattering spectrum. 5,[7][8][9] To gain more information, such as the phase of the plasmon, 10 or to improve sensitivity, a more complicated optical system is often required, for example with interferometric techniques, [11][12][13][14][15][16][17][18][19][20][21][22][23][24] spectroscopic ellipsometry, [25][26][27][28][29] the addition of magnetic materials for magneto-optical SPR sensing, 30 or the addition of gain media for detection with plasmon laser systems. 31 Among these, interferometric techniques are useful not only for sensing, but also for more complete device characterization.…”

Ultra broadband phase measurements on nanostructured metasurfaces

“…Due to restrictions of the state-of-the-art experimental techniques for the phase measurements on metasurfaces, the preference is commonly given to indirect characterization methods relying heavily on rigorous numerical simulations. [6][7][8][9][10][11][12] Here, we demonstrate, based on the Kramers-Kronig transformation analysis, that the use of indirect methods is inadequate for the accurate characterization of complex metasurfaces. In order to provide experimental access to the complex transmission and reflection coefficients of optical metasurfaces and as a prerequisite to assess their broadband performance, we developed an original experimental technique.…”

“…This extreme bandwidth together with the lacking necessity of additional physical assumptions, structuring of the samples, or demanding gauging procedures are the key features distinguishing the approach from previously proposed methods for phase measurements on metamaterials and metasurfaces. [6][7][8][9][10][11][12] Shaping light propagation in optically passive media commonly requires the information on the light dispersion in a material, an issue that in the case of metasurfaces can be reduced to the problem of finding complex transmission and reflection coefficients tðkÞ and rðkÞ. A main feature of metasurfaces is their capability of strong and resonant light interaction with the constitutive plasmonic nanostructures.…”

Complex k band diagrams of 3D metamaterial/photonic crystals

“…A method of solving for complex wavenumber dispersion curves using the FEM has been proposed [1,2] but only for 2D crystals. The benefits of the complex wavenumber 2D FEM are becoming better appreciated and use of this method is becoming more common [13,14,15,16,17]. It is therefore timely to generalize this method of Complex Wavenumber Eigenvalue Simulations (CWES) from two to three dimension, which is the object of this paper.…”