Near-Field Excited Archimedean-like Tiling Patterns in Phonon-Polaritonic Crystals

Abstract

Phonon-polaritons (PhPs) arise from the strong coupling of photons to optical phonons. They offer light confinement and harnessing below the diffraction limit for applications including sensing, imaging, superlensing, and photonics-based communications. However, structures consisting of both suspended and supported hyperbolic materials on periodic dielectric substrates are yet to be explored. Here we investigate phonon-polaritonic crystals (PPCs) that incorporate hyperbolic hexagonal boron nitride (hBN) to a silicon-based photonic crystal. By using the near-field excitation in scattering-type scanning near-field optical microscopy (s-SNOM), we resolved two types of repetitive local field distribution patterns resembling the Archimedean-like tiling on hBN-based PPCs, i.e., dipolar-like field distributions and highly dispersive PhP interference patterns. We demonstrate the tunability of PPC band structures by varying the thickness of hyperbolic materials, supported by numerical simulations. Lastly, we conducted scattering-type nanoIR spectroscopy to confirm the interaction of hBN with photonic crystals. The introduced PPCs will provide the base for fabricating essential subdiffraction components of advanced optical systems in the mid-IR range.

Hyperspectral Nanoimaging of van der Waals Polaritonic Crystals

“…We note that a similar work was published after submission of our manuscript. It reports a near-field study of an h-BN polaritonic crystal that was obtained by periodic structuring of the SiO 2 substrate (rather than the h-BN flake by itself).…”

“…It also could become an essential tool for experimental exploration of nontrivial features in band structures (such as, e.g., Weyl or Dirac points) and related electromagnetic bound states. 34,35 We note that a similar work 36 was published after submission of our manuscript. It reports a near-field study of an h-BN polaritonic crystal that was obtained by periodic structuring of the SiO 2 substrate (rather than the h-BN flake by itself).…”

“…It reports a near-field study of an h-BN polaritonic crystal that was obtained by periodic structuring of the SiO 2 substrate (rather than the h-BN flake by itself). In contrast to hyperspectral nanoimaging and connecting near-field images with LDOS (as reported in our work), ref reports near-field spectra at individual positions and focuses on the discussion of the Archimedean-like polaritonic patterns observed by s-SNOM imaging.…”

Based On Confined Polymerization: In Situ Synthesis of PANI/PEEK Composite Film in One‐Step

“…With regard to the small‐scale analysis, it shows that PANI is well dispersed inside the film, and there is no obvious interface with the characteristic peak of PEEK (absorption peak at 1650 cm −1 ). (Figure 2i,j ) [ 59 , 60 ] The Nano‐IR shows that PANI and PEEK are interlaced with each other, and no phase separation occurs. During the growth process of PANI, it grows in the free volume of PEEK.…”

Twisted Polaritonic Crystals in Thin van der Waals Slabs

“…PCs based on anisotropic polar vdW materials (such as h-BN) have demonstrated interesting possibilities for enhanced light-matter interactions (11)(12)(13) and topological photonics (14). On the other hand, PCs in in-plane anisotropic materials, where the manipulation of polaritons can exhibit more degrees of freedom, have not yet been addressed.…”