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arXiv · 2404.05450

Cross-Dimensional Exciton Coupling in Quantum Dot - Carbon Nanotube Hybrid Thin Films

Anna Wroblewska·Niclas S. Mueller·Mariusz Zdrojek·Stephanie Reich·Georgy Gordeev
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Abstract

Dipole-dipole interactions provide a route to couple excitons across materials of different dimensionality. Here, we introduce hybrid films as a cross-dimensional excitonic platform and develop a theory of resonant Raman scattering in the presence of dipolar exciton coupling. Combining a coupled-oscillator model with perturbation theory, we show that coupling renormalizes the exciton-photon matrix elements and modifies nanotube Raman excitation profiles. We test this framework in vacuum-filtered films containing InP/ZnS quantum dots and mixed chirality metallic single-walled carbon nanotubes. The quantum-dot exciton remains near 1.83 eV, while chirality-dependent nanotube excitons span 1.7-1.93 eV, enabling systematic control of excitonic detuning. Relative to pristine nanotube films, the hybrids exhibit detuning-dependent redshifts and blueshifts, Raman intensity enhancement, reduced effective linewidths, and near-resonant two-branch profiles. The model yields an effective splitting of approximately 110 meV. Resonant Raman scattering thus provides component-selective access to dipolar interactions that are only weakly apparent in ensemble absorption spectra.

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Anna Wroblewska, Niclas S. Mueller, Mariusz Zdrojek, Stephanie Reich, Georgy Gordeev. 2024-04-08. Cross-Dimensional Exciton Coupling in Quantum Dot - Carbon Nanotube Hybrid Thin Films. https://arxiv.org/abs/2404.05450

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