Surface Polariton-Like s-Polarized Waveguide Modes in Switchable Dielectric Thin-Films on Polar Crystals
arXiv:1906.10593 · doi:10.1002/adom.201901056
Abstract
Surface phonon polaritons (SPhP) and surface plasmon polaritons (SPP), evanescent modes supported by media with negative permittivity, are a fundamental building block of nanophotonics. These modes are unmatched in terms of field enhancement and spatial confinement, and dynamical all-optical control can be achieved e.g. by employing phase-change materials (PCMs). However, the excitation of surface polaritons in planar structures is intrinsically limited to p-polarization. On the contrary, waveguide modes in high-permittivity films can couple to both p- and s-polarized light, and in thin films, their confinement can become comparable to surface polaritons. Here we demonstrate that the s-polarized waveguide mode in a thin GeSbTe (GST) film features a similar dispersion, confinement, and electric field enhancement as the SPhP mode of the silicon carbide (SiC) substrate, while even expanding the allowed frequency range. Moreover, we experimentally show that switching the GST film grants non-volatile control over the SPhP and the waveguide mode dispersions. We provide an analytical model for the description of the GST/SiC waveguide mode and show that our concept is applicable to the broad variety of polar crystals throughout the infrared spectral range. As such, complementarily to the polarization-limited surface polaritons, the s-polarized PCM waveguide mode constitutes a promising additional building block for nanophotonic applications.
References in corpus (13)
- Gate-tuning of graphene plasmons revealed by infrared nano-imaging
- Sub-diffractional, volume-confined polaritons in a natural hyperbolic material: hexagonal boron nitride
- Generalized 4 4 Matrix Formalism for Light Propagation in Anisotropic Stratified Media: Study of Surface Phonon Polaritons in Polar Dielectric Heterostructures
- Time-Domain Separation of Optical Properties From Structural Transitions in Resonantly Bonded Materials
- Reconfigurable Mid-Infrared Hyperbolic Metasurfaces using Phase-Change Materials
- Polariton Nanophotonics using Phase Change Materials
- Active Tuning of Surface Phonon Polariton Resonances via Carrier Photoinjection
- Strong Coupling of Epsilon-Near-Zero Phonon Polaritons in Polar Dielectric Heterostructures
- Resonant enhancement of second harmonic generation in the mid-infrared using localized surface phonon polaritons in sub-diffractional nanostructures
- Phase change materials for nano-polaritonics: a case study of hBN/VO2 heterostructures
- Second Harmonic Generation from Phononic Epsilon-Near-Zero Berreman Modes in Ultrathin Polar Crystal Films
- Second Harmonic Generation from Critically Coupled Surface Phonon Polaritons
- Controlling Nanoscale Air-Gaps for Critically Coupled Surface Polaritons by Means of Non-Invasive White-Light Interferometry