StatusThe thesis was presented on the 26 April, 2019
Approved by NCAA on the 9 July, 2019
Abstract– 0.86 Mb / in romanian
ThesisCZU 535.2/.3 (043.2)
6.62 Mb /
Thesis structure. The Ph.D. thesis comprises the introduction, four chapter, conclusions bibliography (151 titles), 7 appendixes, 139 pages of main text, 78 figures and 2 tables. The obtained results are published in 50 scientific articles.
Domain of study consists in the study of anisotropy and spectroscopy of excitonic polaritons of birefringent ZnAs2 crystals, In0,3Ga0,7As/GaAs nanostructures and estimation of basic optic properties and constants.
The scopes of the papers consists in the experimental study of anisotropy of semiconductor crystals with reduced symmetry, establishing the mechanisms of anisotropy of optical properties, study of phenomena at the crystals’ surface and at the interfaces of metal and other semiconductors, elucidating the practical applications of optical and photoelectric dichroism, study of parameters and properties of In0,3Ga0,7As/GaAs quantum well structures with the aim of developing optoelectronic devices.
The scientific novelty and originality consists in the characterization of optical properties of birefringent materials and structures with quantum wells and the determination of fundamental optical parameters at high resolution. The originality of the proposed solutions is to determine the possibility of developing optoelectronic devices sensitive to the polarization of optical radiation used in optical communication systems and other domains.
The solved scientific problem lies in the determination and calculation of the fundamental optical parameters of excitonic polaritons in ZnAs2 birefringent crystals with C2h5 symmetry and of the electronic transitions in the fundamental absorption band of anisotropic materials and heterostructures with quantum wells for optoelectronic devices development purposes.
The theoretical significance of the paper is the calculation of spectra of ZnAs2 excitonic polaritons based on the dispersion relations, the determination of the effective masses of electrons and holes, determination of fundamental optical parameters using Kramers-Kronig relations for ZnAs2 crystals and heterostructures with quantum wells.
The applicative value of the paper is the demonstration of the possibility of developing electronic devices sensitive to linear polarized radiation based on ZnAs2 anisotropic crystals and the objective estimation of the quality and parameters of heterostructures with quantum wells using optical spectroscopy methods.