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Information × Registration Number 0212U004584, 0111U005561 , R & D reports Title Sensors to detect toxic molecules popup.stage_title Head Strelchuk Viktor Vasylyovych, Доктор фізико-математичних наук Registration Date 20-01-2012 Organization Institute of Semiconductor Physics of National Academy of Sciences of Ukrain popup.description2 Two-period structures with and without vertical coupling between indirect and direct bandgap InAs quantum dots (QDs) both with type I band alignment, grown by molecular-beam epitaxy, were investigated by confocal Raman and photoluminescence (PL) microspectroscopy. The observed blue shift of PL band of the indirect (direct) bandgap QD by 20 (80) meV with decrease of thickness of Ga(Al)As intermediate layer between two InAs QD layers from 30 to 8 nm is considered as caused by increase of elastic strains (decrease of QDs sizes) in QD layers and by coupling between QDs electronic states. Scanning confocal resonant Raman microspectroscopy was applied for non-destructive evaluation of composition at various depths along the thickness of vertical coupling of the upper InAs/AlGaAs and lower InAs/AlAs QDs layers of the sandwich structures. Based on the analysis of determined from the in-depth Raman spectra optical phonons frequencies, the depth distribution of composition in InAlAs and GaAlAs alloy layers formed as a result of strain-driven enhanced interdiffusion was determined. Product Description popup.authors Авраменко Катерина Андріївна Коломис Олександр Федорович Ніколенко Андрій Сергійович popup.nrat_date 2020-04-02 Close