학술논문

Bloch Surface Waves in Open Fabry–Perot Microcavities
Document Type
Academic Journal
Source
Micromachines. February, 2023, Vol. 14 Issue 3
Subject
Language
English
ISSN
2072-666X
Abstract
Thanks to the increasing availability of technologies for thin film deposition, all-dielectric structures are becoming more and more attractive for integrated photonics. As light–matter interactions are involved, Bloch Surface Waves (BSWs) may represent a viable alternative to plasmonic platforms, allowing easy wavelength and polarization manipulation and reduced absorption losses. However, plasmon-based devices operating at an optical and near-infrared frequency have been demonstrated to reach extraordinary field confinement capabilities, with localized mode volumes of down to a few nanometers. Although such levels of energy localization are substantially unattainable with dielectrics, it is possible to operate subwavelength field confinement by employing high-refractive index materials with proper patterning such as, e.g., photonic crystals and metasurfaces. Here, we propose a computational study on the transverse localization of BSWs by means of quasi-flat Fabry–Perot microcavities, which have the advantage of being fully exposed toward the outer environment. These structures are constituted by defected periodic corrugations of a dielectric multilayer top surface. The dispersion and spatial distribution of BSWs’ cavity mode are presented. In addition, the hybridization of BSWs with an A exciton in a 2D flake of tungsten disulfide (WS[sub.2]) is also addressed. We show evidence of strong coupling involving not only propagating BSWs but also localized BSWs, namely, band-edge and cavity modes.
Author(s): Niccolò Marcucci [1]; Tian-Long Guo [2]; Ségolène Pélisset [2]; Matthieu Roussey [2]; Thierry Grosjean [3]; Emiliano Descrovi (corresponding author) [1,*] 1. Introduction The existence of optical modes strongly confined [...]