Article
Crystallography
Ainash Zhumazhanova, Alisher Mutali, Anel Ibrayeva, Vladimir Skuratov, Alma Dauletbekova, Ekaterina Korneeva, Abdirash Akilbekov, Maxim Zdorovets
Summary: A depth-resolved Raman spectroscopy technique was used to study residual stress profiles in polycrystalline silicon nitride irradiated with Xe and Bi ions. Both compressive and tensile stress fields were identified, separated by a buffer zone at a depth coinciding with the thickness of an amorphous layer. The size of the amorphous layer was evaluated from the dose dependence of the Raman spectra.
Article
Nuclear Science & Technology
R. A. Rymzhanov, A. Akzhunussov, A. E. Volkov, A. D. Ibrayeva, V. A. Skuratov
Summary: The effect of ion irradiation on thermal transport in alumina was studied using molecular dynamics simulation. It was found that increasing ion flux leads to a decrease in thermal conductivity of alumina. The experimental and simulated results are in reasonable agreement, and it was observed that the highly damaged core of ion tracks has a significant impact on heat transport.
NUCLEAR MATERIALS AND ENERGY
(2022)
Article
Materials Science, Multidisciplinary
Azat Abdullaev, Ainur Koshkinbayeva, Vinay Chauhan, Zhangatay Nurekeyev, Jacques O'Connell, Arno Janse van Vuuren, Vladimir Skuratov, Marat Khafizov, Zhandos N. Utegulov
Summary: Thermal transport in swift heavy ion (SHI) irradiated insulating single crystalline oxide materials was investigated. The study revealed that different materials were affected by different forms of damage, resulting in a decrease in thermal conductivity. It was also found that materials with lower penetrating thermal waves were more likely to form surface hillocks. An analytical model and depth profiling were used to determine the depth-dependent damage. YAG material had the highest level of damage, while MgO showed the strongest dependence. This research provides important insights into the thermal transport degradation and recovery of oxide ceramics for next-generation nuclear reactor applications.
JOURNAL OF NUCLEAR MATERIALS
(2022)
Article
Chemistry, Physical
M. Karlusic, R. A. Rymzhanov, J. H. O'Connell, L. Brockers, K. Tomic Luketic, Z. Siketic, S. Fazinic, P. Dubcek, M. Jaksic, G. Provatas, N. Medvedev, A. E. Volkov, M. Schleberger
Summary: The experimental study showed that Al2O3 and MgO surfaces exhibit distinct nanometric modifications when irradiated with 23 MeV I beam at a grazing incidence angle compared to normal incidence. Numerical simulations revealed that the presence of the surface inhibits recrystallization process, preventing transient tracks from recovery and forming observable nanopatterns. The differences in viscosities in molten states between Al2O3 and MgO explain the variation in nanostructures created on the surfaces.
SURFACES AND INTERFACES
(2021)
Article
Chemistry, Physical
Sanjeev Kumar, J. Shakya, T. Mahanta, D. Kanjilal, T. Mohanty
Summary: This study investigates the effects of swift heavy ion irradiation on the optical and surface electronic properties of chemical vapor deposited (CVD) graphene sheets. The results show that the sputtered substrate atoms become trapped in the graphene sheet and alter its Fermi level, as confirmed by Raman spectroscopy and scanning Kelvin probe microscopy. Monte Carlo simulations using SRIM and TRIM packages further study the mechanism of ion interaction and its effects on graphene and substrate materials.
SURFACES AND INTERFACES
(2022)
Article
Materials Science, Multidisciplinary
R. Assylbayev, A. Akilbekov, G. Baubekova, K. Chernenko, M. Zdorovetz, E. Feldbach, E. Shablonin, A. Lushchik
Summary: This study investigates low-temperature cathodo- and photoluminescence in MgO single crystals, specifically the F and F+ centers as well as bivacancies. The results show that the cathodoluminescence bands associated with the F, F+ and P centers strengthen with Xe-irradiation fluence up to 10(13) ions/cm(2), but experience drastic emission attenuation at higher fluences. The limitations of using luminescence methods for detecting structural point defects induced by heavy irradiation are also discussed.
Article
Materials Science, Multidisciplinary
E. A. Korneeva, A. Ibrayeva, A. Janse van Vuuren, L. Kurpaska, M. Clozel, K. Mulewska, N. S. Kirilkin, V. A. Skuratov, J. Neethling, M. Zdorovets
Summary: The results of nanoindentation tests on silicon nitride irradiated with different ions showed that there was insignificant change in hardness for ions with electronic stopping power less than the threshold of latent track formation, while accumulation of latent tracks produced by Xe and Bi ions resulted in first hardening and then softening of irradiated silicon nitride.
JOURNAL OF NUCLEAR MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Lei Yang, Qi-Jun Liu, Xue Yang, Fu-Sheng Liu
Summary: Raman spectra of sulfur under rapid unloading rate showed discontinuous relative area ratios Av1, v2/Av3 (v1 at 156 cm-1, v2 at 217 cm-1, and v3 at 475 cm-1) with increasing pressure. A phase transition is likely to occur around 1.41 GPa, indicated by the breakpoint. At a higher pressure of 5.45 GPa, sulfur exhibited amortization accompanied by a light absorption spectrum, suggesting a unique amorphization phenomenon under impact loading.
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
(2023)
Article
Chemistry, Multidisciplinary
Denis Machon, Sylvie Le Floch, Shashank Mishra, Stephane Daniele, Karine Masenelli-Varlot, Patrick Hermet, Patrice Melinon
Summary: Ti0.5Sn0.5O2 nanoparticles of different sizes were studied under high pressure using Raman spectroscopy. The results showed a phase transition in particles with a diameter of 10 nm at 20-25 GPa, while no phase transition was observed in particles with a diameter of 5 nm up to 30 GPa. The Ti0.5Sn0.5O2 solid solution exhibited extended stability at the nanoscale, thanks to the mixing of Ti and Sn.
Article
Chemistry, Physical
Abdirash Akilbekov, Arseny Kiryakov, Guldar Baubekova, Gulnara Aralbayeva, Alma Dauletbekova, Aiman Akylbekova, Zhulduz Ospanova, Anatoli I. Popov
Summary: This study examined the optical properties of magnesium-aluminate spinel after being irradiated with 220 MeV Xe ions to simulate the impact of nuclear fuel fission fragments. The experiments measured transmission spectra, optical absorption spectra, and Raman spectra. The results showed new absorption peaks and disordering of the crystal structure. Raman spectroscopy proved to be an effective method for detecting structural changes in the crystals.
Article
Engineering, Electrical & Electronic
S. Rajesham, K. Chandra Sekhar, Md Shareefuddin, J. Siva Kumar
Summary: This manuscript discusses the preparation and detailed physical and structural study of B2O3-CdO-Al2O3-PbF2 glasses reinforced with MoO3 ions. The addition of MoO3 resulted in a decrease in density and band gap values, and an increase in refractive index, indicating the transformation of Mo6+ ions to Mo5+ ions and the formation of NBOs in the glasses. FTIR spectra revealed the presence of different borate and aluminate units, as well as the conversion of Mo6+ ions to Mo5+ ions. The Raman spectra showed the effect of MoO3 ions, indicating the conversion of BO4 to BO3 units and the increase in NBOs, providing an explanation for the density variation.
OPTICAL AND QUANTUM ELECTRONICS
(2022)
Article
Materials Science, Multidisciplinary
Fang Yuan, Zheng Zhao, Yanling Zhang, Tuo Wu
Summary: The effect of Al2O3 content on the viscosity and structure of CaO-SiO2-Cr2O3-Al2O3 slags was investigated. The results showed that within a certain range, the viscosity of the slag is significantly influenced by the Al2O3 content, and the Cr2O3-containing slag requires less Al2O3. Raman spectra revealed structural changes in the slag, and the dissolved organic phosphorus content correlated with the viscosity and Raman results.
INTERNATIONAL JOURNAL OF MINERALS METALLURGY AND MATERIALS
(2022)
Article
Chemistry, Physical
Koushik Bhandari, V. Grover, P. Kalita, K. Sudarshan, B. Modak, Saurabh K. Sharma, P. K. Kulriya
Summary: This study investigates the radiation response of YAG and Nd-YAG materials under varying irradiation doses. The results show a decrease in crystallinity with increasing dose, with Nd-YAG being more severely damaged. The formation of oxygen vacancies in Nd-YAG contributes to radiation damage. Comparison with other materials reveals a relatively poorer radiation response of YAG.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Materials Science, Ceramics
Shagufta Gulbadan, Muhammad Azhar Khan, Raqiqa Tur Rasool, Taharh Zelai, Khalid Mahmood, Muhammad Shahid, Altaf Hussain
Summary: The sol-gel auto-combustion process was used to synthesize M-type hexagonal ferrite powder samples with the chemical formula Ba0.3Sr0.7-xCoxFe12-ySmyO19 (x = 0-0.5, y = 0-0.05). The samples were analyzed using X-ray diffraction technique (XRD), Raman, and photoluminescence spectroscopies. The results showed that the samples possessed a hexagonal structure and had the impurity phase alpha-Fe2O3. The samples demonstrated semiconductor properties with a bandgap energy of 1.875 eV and were found to be suitable for microwave and high-frequency applications.
CERAMICS INTERNATIONAL
(2023)
Article
Chemistry, Inorganic & Nuclear
Ting Geng, Shuai Wei, Wenya Zhao, Zhiwei Ma, Ruijing Fu, Guanjun Xiao, Bo Zou
Summary: The study explores the structure-property relationship of Cs3Bi2Br9 NCs using high pressure techniques, revealing changes in band gap and phase transition under pressure. The research demonstrates the reversible nature of these changes and their influence on orbital interactions, impacting the material's potential applications. This work contributes to a better understanding of Cs3Bi2Br9 NCs and presents pressure processing as an efficient and environmentally friendly strategy for material design.
INORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Physics, Applied
Savita, Megha Jain, Manju, Anil Kumar Sinha, Fouran Singh, Ankush Vij, Anup Thakur
Summary: The study investigated the influence of combustion fuels on the radiative defects of MgAl2O4 spinel, revealing that different fuel types can affect the types and concentrations of structural defects in the samples. Spectral analysis revealed the presence of related defect centers in spinel and highlighted various intrinsic defects in the spinel.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Physics, Condensed Matter
Himanshi Gupta, Jitendra Singh, G. R. Umapathy, Vijay Soni, S. Ojha, Soumen Kar, Fouran Singh
Summary: Ga x Zn1-x O thin films with varying Ga fraction were irradiated with heavy ions, resulting in a decrease in transmittance and an increase in Urbach energy. The presence of localized states influenced charge transport and electrical conductivity, with different dominant conduction mechanisms observed at different temperature regimes. Higher ion fluence and doping fraction led to strong carrier localization in the films, causing a sudden rise in resistivity at low temperatures.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2021)
Article
Chemistry, Multidisciplinary
R. C. Ramola, Sandhya Negi, Mukesh Rawat, R. C. Singh, Fouran Singh
Summary: Zinc oxide (ZnO) is a versatile material with high thermal conductivity, electron mobility, wide band gap, and exciton binding energy, making it suitable for various device applications. Among these applications, gallium-doped ZnO thin films annealed at 700 degrees Celsius show the highest sensitivity and shortest response and recovery time for ethanol and acetone gases, demonstrating the potential for gas sensing applications.
Article
Instruments & Instrumentation
Satyanarayana S. Reddy, H. S. Lokesha, K. R. Nagabhushana
Summary: High-sensitive spectroscopy instruments have been developed for measuring TLE, diffuse reflectance, and PL with features like low cost, high resolution, and compact size. The recorded spectra of Al2O3 and ZnO provide valuable information for materials science research, enabling investigation of optical properties through TLE, PL, and diffuse reflectance measurements.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2021)
Article
Chemistry, Physical
H. S. Lokesha, K. R. Nagabhushana, Fouran Singh, S. H. Tatumi, A. R. E. Prinsloo, C. J. Sheppard
Summary: The study examined the defects and spectroscopic properties of monoclinic ZrO2 and ZrO2:Sm3+ phosphor under 100 MeV Si7+ ion excitation utilizing ion beam analysis methods. Various experimental techniques were used to evaluate the structural parameters and properties of the samples, revealing characteristic emission peaks and transitions under ion excitation. Additionally, the thermal spike model was implemented to estimate the ion track radius and local temperature induced by ion excitation.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Materials Science, Multidisciplinary
Ratnesh Gupta, K. Sangeeth, M. Gupta, R. J. Choudhary, A. Sagdeo, F. Singh, Ajay Gupta
Summary: The FeCo/CoO bilayer shows exchange bias at 10K, with the value being enhanced by thermal annealing. X-ray diffraction confirms the phase formation in the CoO layer, and a correlation is observed between soft X-ray absorption and magnetic characteristics. Ion irradiation affects the exchange bias value, with higher ion fluence reducing the value due to defects in the film.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2022)
Article
Nuclear Science & Technology
Paramita Patra, Sejal Shah, M. Toulemonde, I Sulania, F. Singh
Summary: Ion beam irradiation can induce changes in properties and performance of materials. The study investigates damage in Al2O3 caused by 100 MeV Au ions using different thermal spike models and experiments with swift heavy ion irradiation. Characterization techniques such as GIXRD, AFM, and PL spectroscopy show structural changes and defects in the material after irradiation.
RADIATION EFFECTS AND DEFECTS IN SOLIDS
(2022)
Article
Chemistry, Physical
Alvaro de Farias Soares, Sonia Hatsue Tatumi, Lilia Coronato Courrol, Renata de Faria Barbosa, Nagabhushana Kuruduganahalli Ramachandraiah
Summary: This study reports the structure, composition, luminescence properties, and transfer phenomena in Brazilian natural fluorapatite. The results show that the sample exhibits photoluminescence, thermoluminescence, and optically stimulated luminescence, as well as phenomena such as photothermo transfer.
RADIATION PHYSICS AND CHEMISTRY
(2022)
Article
Physics, Condensed Matter
H. S. Lokesha, K. R. Nagabhushana, Fouran Singh, N. R. Thejavathi, Sonia Hatsue Tatumi, A. R. E. Prinsloo, C. J. Sheppard
Summary: This study investigates the impact of 120 MeV swift Au9+ ion irradiation on the structures of monoclinic, tetragonal, and cubic ZrO2 using X-ray diffraction (XRD) and Raman spectroscopy. The results show a partial phase transition from monoclinic to tetragonal ZrO2, with a transition rate of approximately 74%. Interestingly, a phase transition from cubic to tetragonal ZrO2 was observed under 120 MeV Au9+ ion irradiation. The study discusses the effects of transient temperature, defects, and strain induced by swift heavy ions. This research provides insights into the structural stability of different phases of ZrO2 under swift heavy ion irradiation, which is valuable for selecting potential applications in nuclear reactors, oxygen sensors, accelerators, and radiation shielding.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2023)
Article
Chemistry, Physical
C. Lakshmi Ranganatha, H. S. Lokesha, K. R. Nagabhushana, B. S. Palakshamurthy
Summary: This study investigates the structure, photoluminescence, thermoluminescence, and optically stimulated luminescence of SrMoO4 phosphor, and analyzes its kinetics. The SrMoO4 sample has a tetragonal structure and agglomerated particles with a size of about 5.8 ± 1.2 μm. Photoluminescence exhibits a broad peak at 490 nm when excited at 288 nm. Thermoluminescence shows two peaks at 365 K and 472 K. The study provides insights into the properties and potential applications of SrMoO4.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Analytical
H. S. Lokesha, K. R. Nagabhushana, S. H. Tatumi, R. R. Rocca, Fouran Singh
Summary: Zr1-xCexO2 samples with different Ce concentrations were synthesized using a combustion technique. X-ray diffraction results showed that Ce-doped ZrO2 nanoparticles exhibited a monoclinic structure up to 1 mol% Ce concentration, and a mixed phase (monoclinic + tetragonal) beyond that concentration. The crystallite size decreased and the strain increased with increasing Ce concentration. Photoluminescence spectra indicated a blue emission in Zr1-xCexO2 samples, with the highest intensity observed in Zr0.995Ce0.005O2. Thermoluminescence glow curves displayed prominent peaks, and the temperature of the first peak shifted with Ce concentration. Kinetic parameters for the TL peaks were calculated, with Zr0.99Ce0.01O2 showing an activation energy of 0.95 +/- 0.01 eV. These findings suggest potential applications of Zr1-xCexO2 in lighting and radiation dosimeters.
Article
Physics, Multidisciplinary
Harpreet Singh, Palwinder Singh, Kamaljit Singh, Fouran Singh, Abhinav Pratap Singh, Akshay Kumar, Anup Thakur
Summary: This study investigates the effect of swift heavy silver (Ag9+) ion-irradiation on the structural, optical, and morphological properties of SbSe thin films. The films undergo a transition from amorphous to crystalline upon annealing and from crystalline to amorphous upon irradiation. This phase transition results in significant changes in morphology and optical properties, making it suitable for various optoelectronic applications.
Article
Optics
S. Satyanarayana Reddy, K. R. Nagabhushana, N. R. Thejavathi, M. R. Suresh Kumar, Fouran Singh
Summary: This paper presents the thermoluminescence (TL) mechanism of & gamma;-irradiated Al2O3:Tm3+ phosphor. Al2O3:Tm3+ phosphors were synthesized by muffle furnace combustion (MFC) and microwave combustion (MWC). The XRD results showed the stable alpha phase of Al2O3 in both MFC and MWC synthesized samples, with crystallite sizes of approximately -99 nm and -147 nm, respectively. The TL glow curves of & gamma; -irradiated Al2O3:Tm3+ phosphor recorded a prominent peak at -453 K with a shoulder at -500 K. The TL intensity of the prominent peak at 455 K for the MWC synthesized sample was -2.56 times higher than that of the MFC synthesized phosphor.
JOURNAL OF LUMINESCENCE
(2023)
Article
Physics, Applied
H. S. Lokesha, M. L. Chithambo, Sonia Hatsue Tatumi, K. R. Nagabhushana
Summary: The transitions of Pr3+ impurities in monoclinic and cubic phases of ZrO2 were investigated using photoluminescence and thermoluminescence techniques. Zr(1-x)Pr(x)O2 samples (0 ≤x≤0.015) were prepared by the combustion method. Rietveld refined x-ray diffraction results confirmed the presence of mixed monoclinic and cubic structures in Pr-doped ZrO2 samples, while undoped ZrO2 had a monoclinic structure. The effects of Pr doping on the luminescence properties of ZrO2 were observed, including defect-related emission peaks and Pr3+-related emissions at specific wavelengths. The study also revealed that Pr3+ replaces Zr4+ in the cubic lattice sites of ZrO2.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2023)
