Strong Chiro-Optical Activity of Plasmonic Metasurfaces with Inverted Pyramid Arrays

Chiral plasmonics has emerged as a powerful tool for manipulating light at the nanoscale with unprecedented control over light polarization. The advances in nanofabrication have led to the creation of nanostructures that support strong chiroptical responses. However, the complexity of the fabricatio...

Descripción completa

Detalles Bibliográficos
Autores: Pérez, Luis Alberto, Hu, Jinhui, Mendoza Carreño, José, Garriga Bacardi, Miquel, Alonso Carmona, M. Isabel, Arteaga, Oriol, Goñi, Alejandro R., Mihi, Agustín
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:10261/393817
Acceso en línea:http://hdl.handle.net/10261/393817
https://api.elsevier.com/content/abstract/scopus_id/86000180129
Access Level:acceso abierto
Palabra clave:Chiral metasurfaces
High g-factors
Inverted pyramids
Plasmonics
Silicon etching
Descripción
Sumario:Chiral plasmonics has emerged as a powerful tool for manipulating light at the nanoscale with unprecedented control over light polarization. The advances in nanofabrication have led to the creation of nanostructures that support strong chiroptical responses. However, the complexity of the fabrication and the associated high costs remain major challenges in upscaling these architectures. Here, we report on the development of chiral plasmonic metasurfaces composed of inverted pyramid arrays with mismatched directions with respect to the lattice vectors of the array. These metasurfaces are fabricated using a combination of soft lithography and anisotropic etching, resulting in cost-effective and reproducible chiral nanostructures without the need for expensive equipment. The fabricated metasurfaces exhibit high differential transmittance values in the visible spectrum, which are among the highest reported for plasmonic films. Theoretical modeling corroborates the experimental results, demonstrating the significant influence of the mismatch angle on the chiral behavior. Complete polarimetric characterization reveals exceptional chiro-optical activity with circular birefringence exceeding 375°/μm and Kuhn's dissymmetry factors (g-factors) approaching unity.