Raşit Aydin

The electronic properties of a two-electron multi-shell quantum dot-quantum well heterostructure

A detailed investigation of the electronic properties of a double electron in a core/shell/well/shell quantum dot heterostructure has been systematically studied for cases with and without an on-center donor impurity. For this purpose, the Poisson-Schrodinger equations have been solved self-consistently in the frame of the single band effective mass approximation and Hartree treatment. The variation of the binding energies of negatively charged donor impurity (D−) have been examined for different core radii, shell thicknesses, and well widths. The results obtained have been presented comparatively as a function of layer thicknesses and probable physical reasons behind in their behavior have been discussed.

A study of the influences of transition metal (Mn,Ni) co-doping on the morphological, structural and optical properties of nanostructured CdO films

In this paper, a systematic investigations on the effects of transition metals such as Mn and Ni-dopant on physical properties of cadmium oxide (CdO) thin films coated on soda lime glass substrates by using SILAR method have been reported. The characterizations of un-doped, Mn-doped (Cd0.99 Mn0.01O) and Mn/Ni double doped CdO [(Cd0.99−xMn0.01NixO)(0 ≤ x ≤ 0.001)] films were investigated by SEM, EDX, XRD and UV–Vis spectrophotometry to determine the morphological, structural and optical properties, respectively. SEM analysis showed that the surface morphologies of the CdO films were influenced by Mn doping and Mn/Ni co-doping. The EDX result verified the presence of expected elements Cd, O, Mn and Ni in the growing solution. The crystal phases of the samples and their crystallinity quality have been investigated by XRD measurements. The X-ray diffractograms show all the diffraction peaks are highly intense also they demonstrate the preferential orientations of (111) and (200) directions. Optical investigations revealed red shift with Mn doping and Mn/Ni co-doping in the absorbance spectrum.

SILAR yöntemi ile üretilen CuO filmlerin yapısal, morfolojik ve optik özelliklerine ikili katkılamanın (Zn, Li) etkisi

Bu calismada katkisiz CuO ve farkli konsantrasyonlarda Li-katkili Li-ZnCuO filmler cam altliklar uzerine SILAR yontemi ile basarili bir sekilde buyutuldu. Uretilen bu filmler metalurjik mikroskop (MM), X-isini kirinimi (XRD) ve UV-Vis. spektroskopi ile karakterize edildi. MM sonuclari, CuO filmlerin morfolojisi uzerine Li-Zn ikili katkilama konsantrasyonunun onemli bir etkiye sahip oldugunu gosterdi. XRD verileri filmlerin nanoboyutta kristalize olduklarini ve kristallenme kalitesinin katki konsantrasyonuna bagli olarak degistigini aciga cikardi. Uv-Vis. analiz sonuclari, filmlerin hem optik bant araligi degerlerinde hem de gecirgenliklerinde katki konsantrasyonuna bagli olarak onemli farkliliklarin olustugunu ortaya koydu.