The topic involves the development of scintillation heterostructures with ultrafast, sub-nanosecond luminescence response to ionizing radiation, made from nitride semiconductors by means of organo-metallic epitaxy.
This technological approach enables preparation of material in which atoms are arranged into a crystalline lattice, however individual layers of this quasi-monocrystal can have different chemical composition. Through interleaving such thin layers on the atomic scale, it is possible to prepare quantum heterostructures with diverse functionalities, which find their use in high-tech industrial and healthcare applications. One of the biggest related challenges is to prepare heterostructures with high number of quantum wells in their active layer, so that as large portion as possible of the deeply penetrating ionizing radiation is detected. The technological and luminescence research groups closely cooperate on development of these heterostructures, and they also cooperate with the Crytur company in Turnov.
A snapshot from a transmission electron microscope with atomic resolution, showing a heterostructure with InGaN quantum wells (darker areas). The thickness of quantum wells is roughly 2 atomic layers.