Self-hybridisation between interband transitions and Mie modes in dielectric nanoparticles

Nanophotonics, Journal Year: 2024, Volume and Issue: 13(14), P. 2513 - 2522

Published: Feb. 1, 2024

Abstract We discuss the possibility of self-hybridisation in high-index dielectric nanoparticles, where Mie modes electric or magnetic type can couple to interband transitions material, leading spectral anticrossings. Starting with an idealised system described by moderately high constant permittivity a narrow Lorentzian, which is visible for both plane-wave and electron-beam excitation, we embark on quest realistic systems this effect should be visible. explore variety spherical particles made traditional semiconductors such as Si, GaAs, GaP. With hardly discernible, identify two major causes hindering observation self-hybridisation: very broad fingerprints most candidate materials, significant overlap between nanospheres. thus depart from shape, show that interband–Mie hybridisation indeed feasible example GaAs cylinders, even simple source. This so-far unreported kind polariton has considered when interpreting experimental spectra Mie-resonant nanoparticles assigning modal characters specific features. On other hand, it potential useful characterisation optical properties through control strength via nanoparticle size applications exploit resonances metamaterials, highly-directional antennas, photovoltaics.

Language: Английский

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Linear optical properties of organic microcavity polaritons with non-Markovian quantum state diffusion

Nanophotonics, Journal Year: 2024, Volume and Issue: 13(14), P. 2479 - 2490

Published: Feb. 9, 2024

Abstract Hybridisation of the cavity modes and excitons to polariton states together with coupling vibrational determine linear optical properties organic semiconductors in microcavities. In this article we compute refractive index for such system using Holstein–Tavis–Cummings model then transfer matrix method. We first extract parameters exciton our from fitting experimentally measured absorption a 2,7-bis[9,9-di(4-methylphenyl)-fluoren-2-yl]-9,9-di(4-methylphenyl) fluorene (TDAF) molecular thin film. Then reflectivity film metal clad microcavity by including dispersive mode model. susceptibility systems evolving just single state vector non-Markovian quantum diffusion. The computed location height lower upper polaritons agree experiment within estimated errorbars small angles ( ≤ 30 ° stretchy="false">) $(\le 30{}^{\circ})$ . For larger resonances are error.

Language: Английский

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Cavity Controlled Upconversion in CdSe Nanoplatelet Polaritons

ACS Nano, Journal Year: 2024, Volume and Issue: 18(32), P. 21388 - 21398

Published: July 30, 2024

Exciton-polaritons provide a versatile platform for investigating quantum electrodynamics effects in chemical systems, such as polariton-altered reactivity. However, using polaritons contexts will require better understanding of their photophysical properties under ambient conditions, where chemistry is typically performed. Here, we used cavity quality factor to control strong light–matter interactions and particular the excited state dynamics colloidal CdSe nanoplatelets (NPLs) coupled Fabry–Pérot optical cavity. With increasing factor, observe significant population upper polariton (UP) state, exemplified by rare observation substantial UP photoluminescence (PL). Excitation lower (LP) states results upconverted PL emission from branch due efficient exchange between LP, reservoir dark present collectively polaritonic systems. In addition, measure time scales ∼100 ps, implying great potential NPL based systems affect photochemical reaction rates. State-of-the-art dynamical simulations show outstanding quantitative agreement with experiments, thus important insight into nanocrystal-based These findings represent step toward development practical photochemistry platforms.

Language: Английский

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Direct Quantification of the Plasmon Dephasing Time in Ensembles of Gold Nanorods Through Two-Dimensional Electronic Spectroscopy

Nanoscale Advances, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

In this study, we used two-dimensional electronic spectroscopy to examine the early femtosecond dynamics of suspensions colloidal gold nanorods with different aspect ratios. all samples, signal distribution in 2D maps at timescale shows a distinctive dispersive behavior, which can be explained by interference between exciting field and produced on nanoparticle's surface collective motion electrons when plasmon is excited. Studying effect, active only until has been dephased, allows for direct estimation dephasing time an ensemble particles. Our findings provide insight into fundamental behavior plasmonic states highlight potential uncovering ultrafast coherent optical phenomena nanoscale.

Language: Английский

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Polariton-induced Purcell effects via a reduced semiclassical electrodynamics approach

The Journal of Chemical Physics, Journal Year: 2025, Volume and Issue: 162(12)

Published: March 24, 2025

Recent experiments have demonstrated that polariton formation provides a novel strategy for modifying local molecular processes when large ensemble of molecules is confined within an optical cavity. Herein, numerical based on coupled Maxwell–Schrödinger equations examined simulating in realistic cavity structure under collective strong coupling. In this approach, only few molecules, referred to as quantum impurities, are treated mechanically, while the remaining macroscopic layer and modeled using dielectric functions. When single electronic two-level system embedded Lorentz medium two-dimensional Bragg resonator, our simulations reveal polariton-induced Purcell effect: radiative decay rate impurity significantly enhanced by frequency matches frequency, can sometimes be greatly suppressed near resonance with bulk forming addition, approach demonstrates absorption light exhibits Rabi-splitting-dependent suppression due inclusion structure. Our also identify fundamental limitation approach—an inaccurate description dephasing rates into dark modes. This arises because dark-mode degrees freedom not explicitly included most simple As effect alters differently from weak coupling, may facilitate understanding origin polariton-modified photochemistry

Language: Английский

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