@article{LiShanRupprechtetal.2022,
  author    = {Li, Donghai and Shan, Hangyong and Rupprecht, Christoph and Knopf, Heiko and Watanabe, Kenji and Taniguchi, Takashi and Qin, Ying and Tongay, Sefaattin and Nuß, Matthias and Schr{\"o}der, Sven and Eilenberger, Falk and H{\"o}fling, Sven and Schneider, Christian and Brixner, Tobias},
  title     = {Hybridized exciton-photon-phonon states in a transition-metal-dichalcogenide van-der-Waals heterostructure microcavity},
  series = {Physical Review Letters},
  journal   = {Physical Review Letters},
  edition   = {accepted version},
  issn      = {1079-7114},
  doi       = {10.1103/PhysRevLett.128.087401},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-351303},
  year      = {2022},
  abstract  = {Excitons in atomically thin transition-metal dichalcogenides (TMDs) have been established as an attractive platform to explore polaritonic physics, owing to their enormous binding energies and giant oscillator strength. Basic spectral features of exciton polaritons in TMD microcavities, thus far, were conventionally explained via two-coupled-oscillator models. This ignores, however, the impact of phonons on the polariton energy structure. Here we establish and quantify the threefold coupling between excitons, cavity photons, and phonons. For this purpose, we employ energy-momentum-resolved photoluminescence and spatially resolved coherent two-dimensional spectroscopy to investigate the spectral properties of a high-quality-factor microcavity with an embedded WSe\(_2\) van-der-Waals heterostructure at room temperature. Our approach reveals a rich multi-branch structure which thus far has not been captured in previous experiments. Simulation of the data reveals hybridized exciton-photon-phonon states, providing new physical insight into the exciton polariton system based on layered TMDs.},
  language  = {en}
}
@phdthesis{Gross2019,
  author    = {Groß, Heiko},
  title     = {Controlling Light-Matter Interaction between Localized Surface Plasmons and Quantum Emitters},
  doi       = {10.25972/OPUS-19209},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-192097},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2019},
  abstract  = {Metal nanostructures have been known for a long time to exhibit optical resonances via localized surface plasmons. The high electric fields in close proximity to the metal surface have prospects to dramatically change the dynamics of electronic transitions, such as an enhanced spontaneous decay rate of a single emitter. However, there have been two major issues which impede advances in the experimental realization of enhanced light-matter interaction. (i) The fabrication of high-quality resonant structures requires state-of-the-art patterning techniques in combination with superior materials. (ii) The tiny extension of the optical near-field requires precise control of the single emitter with respect to the nanostructure. This work demonstrates a solution to these problems by combining scanning probe and optical confocal microscopy. Here, a novel type of scanning probe is introduced which features a tip composed of the edge of a single crystalline gold sheet. The patterning via focused ion beam milling makes it possible to introduce a plasmonic nanoresonator directly at the apex of the tip. Numerical simulations demonstrate that the optical properties of this kind of scanning probe are ideal to analyze light-matter interaction. Detailed experimental studies investigate the coupling mechanism between a localized plasmon and single colloidal quantum dots by dynamically changing coupling strength via their spatial separation. The results have shown that weak interaction affects the shape of the fluorescence spectrum as well as the polarization. For the best probes it has been found that it is possible to reach the strong coupling regime at the single emitter level at room temperature. The resulting analysis of the experimental data and the proposed theoretical models has revealed the differences between the established far-field coupling and near-field coupling. It has been found that the broad bandwidth of plasmonic resonances are able to establish coherent coupling to multiple transitions simultaneously giving rise to an enhanced effective coupling strength. It has also been found that the current model to numerically calculate the effective mode volume is inaccurate in case of mesoscopic emitters and strong coupling. Finally, light-matter interaction is investigated by the means of a quantum-dot-decorated microtubule which is traversing a localized nearfield by gliding on kinesin proteins. This biological transport mechanism allows the parallel probing of a meta-surface with nm-precision. The results that have been put forward throughout this work have shed new light on the understanding of plasmonic light-matter interaction and might trigger ideas on how to more efficiently combine the power of localized electric fields and novel excitonic materials.},
  subject      = {Plasmon},
  language  = {en}
}
@article{WurdackLundtKlaasetal.2017,
  author    = {Wurdack, Matthias and Lundt, Nils and Klaas, Martin and Baumann, Vasilij and Kavokin, Alexey V. and H{\"o}fling, Sven and Schneider, Christian},
  title     = {Observation of hybrid Tamm-plasmon exciton-polaritons with GaAs quantum wells and a MoSe\(_{2}\) monolayer},
  series = {Nature Communications},
  volume    = {8},
  journal   = {Nature Communications},
  number    = {259},
  doi       = {10.1038/s41467-017-00155-w},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-170480},
  year      = {2017},
  abstract  = {Strong light matter coupling between excitons and microcavity photons, as described in the framework of cavity quantum electrodynamics, leads to the hybridization of light and matter excitations. The regime of collective strong coupling arises, when various excitations from different host media are strongly coupled to the same optical resonance. This leads to a well-controllable admixture of various matter components in three hybrid polariton modes. Here, we study a cavity device with four embedded GaAs quantum wells hosting excitons that are spectrally matched to the A-valley exciton resonance of a MoSe\(_{2}\) monolayer. The formation of hybrid polariton modes is evidenced in momentum resolved photoluminescence and reflectivity studies. We describe the energy and k-vector distribution of exciton-polaritons along the hybrid modes by a thermodynamic model, which yields a very good agreement with the experiment.},
  language  = {en}
}