Browsing by Author "Liebscher, L."

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    White CdS nanoluminophore based tunable hybrid light emitting diodes
    (IEEE, 2007) Nizamoğlu, Sedat; Mutlugün, Evren; Akyüz, Özgün; Kosku-Perkgöz, Nihan; Demir, Hilmi Volkan; Liebscher, L.; Sapra, S.; Gaponik, N.; Eychmüller, A.
    The study aims to fabricate and demonstrate hybrid white light emitting diodes that integrate white emitting CdS nanoluminophores with high light quality. Results show that the white light properties of these hybrid WLED (including (x,y) chromaticity coordinates, color temperature, and color rendering index (Ra)) are conveniently tuned as desired across the white region by controlling the number of these surface state emitting nanoluminophores hybridized on the n-UV LED platform. In this tuning process, with the increasing number of the hybridized surface state emitting nanocrystals, it is observed that (x,y) and Ra increase while Tc decreases.
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    ItemOpen Access
    White emitting CdS quantum dot nanoluminophores hybridized on near-ultraviolet LEDs for high-quality white light generation and tuning
    (Institute of Physics Publishing Ltd., 2008) Nizamoglu, S.; Mutlugun, E.; Akyuz, O.; Perkgoz, N. K.; Demir, Hilmi Volkan; Liebscher, L.; Sapra, S.; Gaponik N.; Eychmüller A.
    To generate white light using semiconductor nanocrystal (NC) quantum dots integrated on light emitting diodes (LEDs), multiple hybrid device parameters (emission wavelengths of the NCs and the excitation platform, order of the NCs with different sizes, amount of the different types of NCs, etc) need to be carefully designed and properly implemented. In this study, we introduce and demonstrate white LEDs based on simple device hybridization using only a single type of white emitting CdS quantum dot nanoluminophores on near-ultraviolet LEDs. Here we present their design, synthesis-growth, fabrication and characterization. With these hybrid devices, we achieve high color rendering index (>70), despite using only a single NC type. Furthermore, we conveniently tune their photometric properties including the chromaticity coordinates, correlated color temperature, and color rendering index with the number of hybridized nanoluminophores in a controlled manner.