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Information × Registration Number 0221U102651, 0118U003046 , R & D reports Title Investigation of delta-doped nanostructures in order of creation of re-tuned by electric field the active and passive devices in the THz range popup.stage_title Head Tulupenko Viktor M., Registration Date 08-02-2021 Organization Donbass State Engineering Academy popup.description2 Object of study: Strained silicon (Si) delta-doped quantum wells with silicon-germanium Si0.8Ge0.2 barriers. Aim of the study: to determine the effect of background and, therefore, deliberate, doping of barriers on the restructuring of, first of all, the first energy spatial quantization levels in delta doped quantum wells. Theoretical results: it is shown that it is possible to obtain an increased (up to two times) concentration of electrons in quantum wells due to the ionization of background impurities. The influence of shallow background impurities in infinite barriers on the real structure of SiGe / Si / SiGe delta-doped quantum well has been studied. Here we consider the case when the symmetry is broken. Necessary modifications of the self-consistent method, which includes the calculation of the impurity binding energy, are explained. The results show that the mentioned asymmetry provides new opportunities for tuning intersubband optical transitions by the degree of ionization of the delta layer impurity. It is also shown that the application of a transverse electric field to a SiGe / Si quantum well with an impurity delta layer inside allows flexible control of the energy gap between the two lower size quantization subbands. The model is based on competition between mini-wells, one of which is created by charge redistribution due to ionization of delta layer impurities, and the other created by the application of an electric field.   Product Description popup.authors Akimov Vladimir I Vasylieva Iryna V Demediuk Roman O Duque Carlos A Tarasov Olexander F Tulupenko Viktor M Fomina Oksana S popup.nrat_date 2021-02-08 Close