arXiv subjects

Elzbieta Guziewicz

Publications and source records attributed to Elzbieta Guziewicz.

4 recordsLinked to original sources

arXiv2026

Structural and Optical Characteristics of $\beta-Ga_2O_3$ Implanted with Rare Earth Ions

We investigated the structural evolution and optical properties of $\beta-Ga_2O_3$ crystals implanted with different rare-earth (RE) ions using channeling Rutherford Backscattering Spectrometry, Positron Annihilation, Photoluminescence, and Photoluminescence Excitation spectroscopies. The studies reveal that implantation-induced disorder, accompanying phase transitions, and post-annealing structural recovery are largely insensitive to the implanted RE species. The defect microstructure is also found to be similar for all implanted RE ions. Thermal annealing does not completely remove radiation-induced defects but instead drives their rearrangement into larger defect complexes. Unimplanted (virgin) $\beta-Ga_2O_3$ exhibits strong UV-visible emission attributed to oxygen vacancies, whereas the introduction of RE ions produces additional emission lines originating from electronic transitions within RE3+ ions. The results indicate that RE3+ ions are excited through the host conduction band, followed by non-radiative relaxation to the 4f excited states and radiative decay to the respective ground states. Fluence-dependent studies of Yb3+ reveal the onset of concentration quenching, while RE-related emission remains efficient even in the presence of substantial lattice disorder. These findings provide new insight into defect evolution in ion-implanted beta-Ga2O3 and clarify the excitation mechanisms of RE3+ ions, offering guidance for optimizing the optical performance of $\beta-Ga_2O_3$:RE materials.

cond-mat.mtrl-sci↗

arXiv2026

Comprehensive structural and optical analysis of differently oriented Yb-implanted $\beta$-Ga$_2$O$_3$

This study presents investigations of Yb-doped $\beta$-Ga$_2$O$_3$, an ultrawide bandgap semiconductor with potential use in future power and optoelectronic devices operating in high-radiation environments. The research has focused on the problem of structural damage caused by the implantation of Yb-ions into three differently oriented crystals and the optical response of created systems. The (001), (010), and (-201)-oriented $\beta$-Ga$_2$O$_3$ crystals were implanted with three different fluences of 150 keV Yb ions and examined using a variety of experimental techniques: high-resolution X-ray diffraction (HRXRD), Rutherford backscattering spectrometry in channeling mode (RBS/c), Raman and photoluminescence (PL) spectroscopies, to provide comprehensive information about studied systems. Furthermore, the RBS/c studies were supported by Monte Carlo simulations. The results show distinctions between differently oriented crystals. In particular, (010)-oriented crystals are characterized by the lowest concentration of extended defects and the presence of compressive stress. In contrast, samples with the other two orientations exhibit tensile stress and significantly higher levels of extended defects. Interestingly, the PL spectra of (010)-oriented $\beta$-Ga$_2$O$_3$ show the lowest emission from Yb$^{3+}$ ions, suggesting that specific types of extended defects, whose formation is more favorable in the other two orientations than in (010), enhance Yb$^{3+}$ luminescence instead of suppressing it.

cond-mat.mtrl-sci↗

arXiv2026

Electronic structure of Sn(1-x)Mn(x)Te semiconducting solid solution: a resonant photoemission study

Manganese-doped tin telluride, Sn(1-x)Mn(x)Te, initially investigated as diluted magnetic semiconductor, has recently attracted considerable attention as a prospective thermoelectric material. The introduction of Mn was found to modify the valence band electronic structure, resulting in an improvement in the Seebeck coefficient and thus, the figure of merit (ZT). In the paper, we present a synchrotron radiation study of the electronic band structure of Sn(0.9)Mn(0.1)Te by resonant photoemission. The contribution of the Mn3d electrons to the valence band (VB), calculated as the difference between the Energy Distribution Curves (EDCs) taken at the maximum and minimum of the Fano resonance for the Mn3p - Mn3d absorption threshold, shows a contribution at the VB edge, a dominant maximum at 4 eV, as well as a wide structure between 7 and 11 eV. Moreover, comparison with undoped SnTe reveals strong renormalization of the Sn5p and Te5p electronic states, which certainly influences the shape of the upper part of the valence band and electron effective mass.

cond-mat.mtrl-sci↗

arXiv2011

Effects related to deposition temperature of ZnCoO films grown by Atomic Layer Deposition - uniformity of Co distribution, structural, optical, electrical and magnetic properties

In the present study we report on properties of ZnCoO films grown at relatively low temperature by the Atomic Layer Deposition, using two reactive organic zinc precursors (dimethylzinc and diethylzinc). The use of these precursors allowed us the significant reduction of a growth temperature to below 300oC. The influence of growth conditions on the Co distribution in ZnCoO films, their structure and magnetic properties was investigated using Secondary Ion Mass Spectroscopy, Scanning Electron Microscopy, Cathodoluminescence, Energy Dispersive X-ray Spectrometry (EDX), X-ray diffraction and Superconducting Quantum Interference Device magnetometry. We achieved high uniformity of the films grown at 160°C. Such films are paramagnetic. Films grown at 200° and at higher temperature are nonuniform. Formation of foreign phases in such films was detected using high resolution EDX method. These samples are not purely paramagnetic and show weak ferromagnetic response at low temperature.

cond-mat.mtrl-sci↗