@article{HeIffLundtetal.2016,
  author    = {He, Yu-Ming and Iff, Oliver and Lundt, Nils and Baumann, Vasilij and Davanco, Marcelo and Srinivasan, Kartik and H{\"o}fling, Sven and Schneider, Christian},
  title     = {Cascaded emission of single photons from the biexciton in monolayered WSe\(_{2}\)},
  series = {Nature Communications},
  volume    = {7},
  journal   = {Nature Communications},
  doi       = {10.1038/ncomms13409},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-169363},
  year      = {2016},
  abstract  = {Monolayers of transition metal dichalcogenide materials emerged as a new material class to study excitonic effects in solid state, as they benefit from enormous Coulomb correlations between electrons and holes. Especially in WSe\(_{2}\), sharp emission features have been observed at cryogenic temperatures, which act as single photon sources. Tight exciton localization has been assumed to induce an anharmonic excitation spectrum; however, the evidence of the hypothesis, namely the demonstration of a localized biexciton, is elusive. Here we unambiguously demonstrate the existence of a localized biexciton in a monolayer of WSe\(_{2}\), which triggers an emission cascade of single photons. The biexciton is identified by its time-resolved photoluminescence, superlinearity and distinct polarization in micro-photoluminescence experiments. We evidence the cascaded nature of the emission process in a cross-correlation experiment, which yields a strong bunching behaviour. Our work paves the way to a new generation of quantum optics experiments with two-dimensional semiconductors.},
  language  = {en}
}
@article{HargartRoyChoudhuryJohnetal.2016,
  author    = {Hargart, F and Roy-Choudhury, K and John, T and Portalupi, S L and Schneider, C and H{\"o}fling, S and Kamp, M and Hughes, S and Michler, P},
  title     = {Probing different regimes of strong field light-matter interaction with semiconductor quantum dots and few cavity photons},
  series = {New Journal of Physics},
  volume    = {18},
  journal   = {New Journal of Physics},
  doi       = {10.1088/1367-2630/aa5198},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-166278},
  year      = {2016},
  abstract  = {In this work we present an extensive experimental and theoretical investigation of different regimes of strong field light-matter interaction for cavity-driven quantum dot (QD) cavity systems. The electric field enhancement inside a high-Q micropillar cavity facilitates exceptionally strong interaction with few cavity photons, enabling the simultaneous investigation for a wide range of QD-laser detuning. In case of a resonant drive, the formation of dressed states and a Mollow triplet sideband splitting of up to 45 μeV is measured for amean cavity photon number <n\(_c\)>\(\leq\) 1. In the asymptotic limit of the linear ACStark effect we systematically investigate the power and detuning dependence of more than 400 QDs. Some QD-cavity systems exhibit an unexpected anomalous Stark shift, which can be explained by an extended dressed 4-levelQDmodel.Weprovide a detailed analysis of the QD-cavity systems properties enabling this novel effect. The experimental results are successfully reproduced using a polaron master equation approach for the QD-cavity system, which includes the driving laser field, exciton-cavity and exciton-phonon interactions},
  language  = {en}
}