Vincent Fellmann

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Ion-induced intermixing and damage is evaluated in GaN/AlN superlattices of quantum dots (QDs) and quantum wells (QWs) using 100 keV Ar(+) implantation at low temperature (15 K). Despite the similar damage build up at low fluences, a significant increase of the damage accumulation takes place for QDs at high fluences. Elemental depth profiles were fitted(More)
PURPOSE The aim of this study was to propose a new clinical diagnostic rating index for secondary caries lesions at crown margins and to correlate this index with histologic evaluations. MATERIALS AND METHODS Based on criteria for the evaluation of root caries, a modification of secondary caries lesions at the crown margin (SC index) was applied; the(More)
Undoped self-assembled GaN quantum dots (QD) stacked in superlattices (SL) with AlN spacer layers were submitted to thermal annealing treatments. Changes in the balance between the quantum confinement, strain state of the stacked heterostructures and quantum confined Stark effect lead to the observation of GaN QD excitonic recombination above and below the(More)
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