Control of the propagation direction of Bound States in the continuum (BICs) in liquid crystal waveguides
A planar waveguide comprises multiple different media layers, where light is confined and transmitted in a film or core sandwiched by cladding media. Light line frequency is an important feature of a waveguide, while waves with frequencies below the light line form a finite number of guided modes th...
| Autor: | |
|---|---|
| Tipo de recurso: | tesis de maestría |
| Fecha de publicación: | 2024 |
| País: | España |
| Institución: | Universitat Politècnica de Catalunya (UPC) |
| Repositorio: | UPCommons. Portal del coneixement obert de la UPC |
| Idioma: | inglés |
| OAI Identifier: | oai:upcommons.upc.edu:2117/423579 |
| Acceso en línea: | https://hdl.handle.net/2117/423579 |
| Access Level: | acceso abierto |
| Palabra clave: | Photonics Liquid crystals Integrated optics Bound state in continuum nematic liquid crystal anisotropic planar waveguide Fotònica Cristalls líquids Òptica integrada Àrees temàtiques de la UPC::Enginyeria de la telecomunicació::Telecomunicació òptica::Fotònica |
| Sumario: | A planar waveguide comprises multiple different media layers, where light is confined and transmitted in a film or core sandwiched by cladding media. Light line frequency is an important feature of a waveguide, while waves with frequencies below the light line form a finite number of guided modes that can propagate in the film, the ones above the light line form a continuum of radiation modes. This thesis will study the bound states in the continuum (BICs) in a planar anisotropic waveguide, which are modes that do not radiate energy away from the film, despite having frequencies above the light line of the waveguide. Two experiments were conducted utilizing reflection spectroscopy to analyze a nematic liquid crystal-based anisotropic planar waveguide. Nematic liquid crystal (LC) is a state of matter that exhibits orientational order but not positional order. The aim was to demonstrate the existence of polarization separable (PS) BICs and the tunability to interferometric (INT) BICs by applying an AC voltage. |
|---|