One challenge with quantum films are point defects such as nitrogen vacancies, which can massively impair the efficiency of light emission. Vasconcellos showed how these point defects can be minimised by specifically controlled temperatures during the growth of the structures and that this can be explained by a diffusion process. In the medium and long term, the work will contribute to an even better understanding of the efficiency of the light emission of such quantum structures. In the longer term, further improved light emitters for other spectral ranges are conceivable. This includes, for example, the work on structured illumination at the nanoscale in QuantumFrontiers or the development of integrated laser sources in Quantum Valley Lower Saxony (QVLS).
For his necessary high-precision measurements, the LENA research centre provided Vasconcellos with first-class large-scale equipment such as the X-ray diffractometer, the FIB/SEM system, the transmission electron microscope and the time-resolved spectroscopy in the OZOS laboratory.
