Real-space visualization of canalized ray polaritons in a single van der Waals thin slab

Polaritons are central to the development of nanophotonics, as they provide mechanisms for manipulating light at the nanoscale. A key advancement has been the demonstration of polariton canalization in which the energy flow is directed along a single direction. An intriguing case is the canalization...

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Detalles Bibliográficos
Autores: Terán-García, Enrique, Lanza, Christian, Voronin, Kirill V., Martín-Sánchez, Javier, Nikitin, Alexey Y., Tarazaga Martín-Luengo, Aitana, Alonso-González, Pablo
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2025
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/391440
Acceso en línea:http://hdl.handle.net/10261/391440
Access Level:acceso abierto
Palabra clave:Canalization
α-MoO3
Phonon polaritons
s-SNOM
Descripción
Sumario:Polaritons are central to the development of nanophotonics, as they provide mechanisms for manipulating light at the nanoscale. A key advancement has been the demonstration of polariton canalization in which the energy flow is directed along a single direction. An intriguing case is the canalization of ray polaritons, characterized by an enhanced density of optical states. Experimental demonstrations of ray polaritons are scarce and their observation in single crystal slabs remains elusive. Here, we propose a novel polaritonic platform based on single thin slabs allowing for the excitation of canalized ray polaritons. By performing near-field nanoimaging, we demonstrate that the necessary conditions for their observation are fulfilled for phonon-polaritons at mid-IR frequencies in thin α-MoO3 slabs on SiO2 substrates. Our real-space images reveal the propagation of unidirectional phonon-polaritons exhibiting a constant propagating phase. These results might impact the development of compact, low-loss optical nanodevices for applications requiring strong light directionality.