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Information × Registration Number 0205U007139, 0103U000197 , R & D reports Title Optical and spectroscopic investigations of semiconductor materials and semiconductor-based structures. popup.stage_title Head Valakh Mykhaylo Yakovych, Доктор фізико-математичних наук Registration Date 22-12-2005 Organization Institute of Semiconductor Physics of National Academy of Sciences of Ukrain popup.description2 The using of optical investigations is actual for examination of the quantum size effect on fundamental physical properties and nanosystem parameters. In combination with microscopic and X-ray techniques, optical methods gives information about the influence of geometrical and structural factors on the energy spectrum peculiarities of the processes realized with participation of electron, exciton, phonon, plasmon and spin excitations. The very this complex approach has been used in this work. The objects under study were molecular beam epitaxy grown heterostructures, quantum wells, superlattices and ensembles of quantum dots based on Ge/Si, CdSe/ZnSe, ZnMnCdSe/ZnSe, AlGaAs/GaAs, SbGaAs/GaAs, InAs/GaAs, InAs/GaSb, InAS/AlSb and InGaP/InGaAs systems. The bulk crystals of layered structure, in particular, BiJ3, PbJ2 and Cs3Bi2J9, have been studied as well. The deviations of the real process of self-induced formation of Ge/Si and InGaAs/GaAs quantum dots from a model Stranski-Krastanov mechanism have beenfound and explained as due to the influence of atomic segregation and anomalously strong interdiffusion. The lateral ordering of the quantum dots and quantum wires in multilayer structures has been proved to be caused by several competing physical factors: anisotropy of the elastic properties of the layers, surface diffusion of adatoms, interaction between the neighboring islands, interaction of deformation fields. It is shown that coupling of localized excitons to LO phonons increases in A2B6 nanostructures. The cooperative states in the vertically correlated pairs of quantum dots have been registered and studied for the first time. Strong optical nonlinearities have been found for the system of laterally aligned InGaAs quantum wires. Product Description popup.authors popup.nrat_date 2020-04-02 Close