Enhanced exciton-to-trion conversion in monolayer MoS2 via nanometrically localized strain at cryogenic temperature
Two-dimensional transition metal dichalcogenides host strongly bound excitonic quasiparticles whose optical response can be tailored by external perturbations. Strain gradients, in particular, provide a powerful route to control exciton-to-trion conversion with nanometric precision, opening opportun...
| Autores: | , , , , , , , , |
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| Tipo de recurso: | artículo |
| Fecha de publicación: | 2025 |
| País: | España |
| Institución: | Universidad Autónoma de Madrid |
| Repositorio: | Biblos-e Archivo. Repositorio Institucional de la UAM |
| Idioma: | inglés |
| OAI Identifier: | oai:dnet:biblosearchi::ffe6a53f6a0dd053a798cf13364bf4a0 |
| Acceso en línea: | https://hdl.handle.net/10486/767080 https://dx.doi.org/10.1016/j.jlumin.2025.121727 |
| Access Level: | acceso abierto |
| Palabra clave: | Exciton-to-trion conversion monolayer MoS 2 Ag nanoparticle chain strain engineering low-temperature photoluminescence Física |
| Sumario: | Two-dimensional transition metal dichalcogenides host strongly bound excitonic quasiparticles whose optical response can be tailored by external perturbations. Strain gradients, in particular, provide a powerful route to control exciton-to-trion conversion with nanometric precision, opening opportunities for excitonic circuitry. Here, we probe nanometrically localized strain fields in monolayer MoS2 transferred onto a linear chain of Ag nanoparticles on LiNbO3 substrates. The nanoparticle chain induces one-dimensional nanoscale strain gradients in the monolayer while its plasmonic resonance remains spectrally detuned from the MoS2 excitonic transitions, ensuring that the observed response arises purely from strain-induced effects. Room temperature spatially resolved photoluminescence shows strain-driven modifications of the excitonic response, consistent with the predicted strain distribution. However, at cryogenic temperatures, the trion-to-exciton emission ratio increases significantly, by around an order of magnitude, near the Ag nanoparticle chain. This indicates a highly efficient, nanometrically localized exciton-to-trion conversion mainly driven by the enhanced strain gradients and the increased funneling efficiency at cryogenic temperatures, where the relative role of drift, and hence funneling efficiency, increases. The results provide direct experimental evidence of the effects of nanoscale, strain-driven trion manipulation at low temperature, achieved without the need for electric gates or advanced lithographic patterning, and underscores nanometer-wide wrinkles formed by the nanoparticle chain as a scalable and versatile strain-engineered platform for reconfigurable excitonic devices and quantum optoelectronics |
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