Spatially resolved measurement of plasmon dispersion using Fourier-plane spectral imaging

Abstract

We show that Fourier-plane imaging in conjunction with the Kretschmann-Raether configuration can be used for measuring polariton dispersion with spatial discrimination of the sample, over the whole visible spectral range. We demonstrate the functionality of our design on several architectures, including plasmonic waveguides, and show that our new design enables the measurement of plasmonic dispersion curves of spatially-inhomogeneous structures with features as small as 3µm, in a single shot.or spectral interrogation, more information is obtained and can be fitted numerically to extract refractive-index changes in the sample. Finally, the possibility to measure the plasmon dispersion in a simple and robust manner can also be used to extract the wavelength-dependent refractive index of an interrogated material, as used in SPP ellipsometry.Here we demonstrate that the concept of Fourier-plane imaging can be further expanded to allow for spatially-resolved dispersion measurements in planar samples supporting surface plasmons. We show that by shaping the illumination beam and incorporating real-space imaging in the optical setup, pre-and post-selection of the interrogated area can be obtained. Therefore, our new optical design offers hybrid functionality and combines the high sensitivity of the broadband dispersion measurements with the imaging capabilities of SPR-imaging techniques. Our measurements show that the lateral detection resolution is high enough to acquire SPP dispersion curves in structures as small as 3µm.

Long-Distance Resonant Energy Transfer Mediated by Hybrid Plasmonic–Photonic Modes

“…As seen in Figure 6a, the fluorescein excitation and emission peaks are around 503 and 523 nm, respectively, whereas the rhodamine B (RhB) has an excitation peak at 555 nm and an emission peak at 577 nm. Next, we used a dedicated single-shot Fourier plane imaging system 41 to measure the angle-resolved reflection of the samples, from which the dispersion of the hybrid cavity can be obtained. Figure 6b shows the dispersion of the sample containing both the donor and acceptor molecules (color image), on which the simulated dispersion for a structure with the same layer thicknesses is superimposed (extracted from the T-matrix calculations presented in Figure 1b).…”