Charge-transfer plasmon polaritons at graphene/α-RuCl3 interfaces

Nanoscale charge control is a key enabling technology in plasmonics, electronic band structure engineering, and the topology of two-dimensional materials. By exploiting the large electron affinity of α-RuCl3, we are able to visualize and quantify massive charge transfer at graphene/α-RuCl3 interface...

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Detalles Bibliográficos
Autores: Rizzo, Daniel J., Jessen, Bjarke S., Sun, Zhiyuan, Ruta, Francesco L., Zhang, Jing, Yan, Jia-Qiang, Xian, Lede, McLeod, Alexander S., Berkowitz, Michael E., Watanabe, Kenji, Taniguchi, Takashi, Nagler, Stephen E., Mandrus, David G., Rubio, Angel, Fogler, Michael M., Millis, Andrew J., Hone, James C., Dean, Cory R., Basov, D. N.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2020
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/235201
Acceso en línea:http://hdl.handle.net/10261/235201
Access Level:acceso abierto
Palabra clave:Plasmon polaritons
Graphene
Scanning near-field optical microscopy
Mott insulators
Descripción
Sumario:Nanoscale charge control is a key enabling technology in plasmonics, electronic band structure engineering, and the topology of two-dimensional materials. By exploiting the large electron affinity of α-RuCl3, we are able to visualize and quantify massive charge transfer at graphene/α-RuCl3 interfaces through generation of charge-transfer plasmon polaritons (CPPs). We performed nanoimaging experiments on graphene/α-RuCl3 at both ambient and cryogenic temperatures and discovered robust plasmonic features in otherwise ungated and undoped structures. The CPP wavelength evaluated through several distinct imaging modalities offers a high-fidelity measure of the Fermi energy of the graphene layer: EF = 0.6 eV (n = 2.7 × 1013 cm–2). Our first-principles calculations link the plasmonic response to the work function difference between graphene and α-RuCl3 giving rise to CPPs. Our results provide a novel general strategy for generating nanometer-scale plasmonic interfaces without resorting to external contacts or chemical doping.