Pub Date : 2023-11-01DOI: 10.12693/aphyspola.144.308
S. Garus, W. Sochacki, J. Garus, M. Šofer, P. Šofer, K.M. Gruszka
{"title":"Influence of Meta-Atom Geometry on the Occurrence of Local Resonance Regions in Two-Dimensional Finite Phononic Structures","authors":"S. Garus, W. Sochacki, J. Garus, M. Šofer, P. Šofer, K.M. Gruszka","doi":"10.12693/aphyspola.144.308","DOIUrl":"https://doi.org/10.12693/aphyspola.144.308","url":null,"abstract":"","PeriodicalId":7164,"journal":{"name":"Acta Physica Polonica A","volume":"8 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139303131","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The samples of FeSe1- xTex (x=0, 0.1, 0.2) were successfully prepared by solvothermal method. The results of X-ray diffraction show that the purity of the samples prepared by the solvothermal method is higher than that of the samples prepared by the solid-state reaction and flux method. The superconducting transition temperature (Tc) of FeSe1-xTex for x=0, 0.1, 0.2 samples is near 9.3 K, 12.4 K, and 13.9 K, respectively, which is a bit higher than that of bulk samples. The electronic structures of these samples are investigated by X-ray photoemission spectroscopy and X-ray absorption spectroscopy. The Fe 2p X-ray photoemission spectroscopy spectra shift to higher binding energy by Te doping due to the increase in hole densities. X-ray photoemission spectroscopy spectra of Se 3d and Te 3d shift to higher binding energy and lower binding energy, respectively, resulting from the charge transfer between Se and Te. It is suggested that the hybridization between Fe 3d and Se 4p is strengthened. Our results imply that the hybridization between Fe 3d and Se 4p probably plays an important role in superconductivity.
{"title":"Study of the Electronic Structure for Te-Doped FeSe Superconductor Prepared by Solvothermal Method","authors":"H.H. Zhao, X.-Y. Jia, J.-D. Shen, Y.-J. Lai, L.-S. Feng, Q. Li","doi":"10.12693/aphyspola.144.247","DOIUrl":"https://doi.org/10.12693/aphyspola.144.247","url":null,"abstract":"The samples of FeSe1- xTex (x=0, 0.1, 0.2) were successfully prepared by solvothermal method. The results of X-ray diffraction show that the purity of the samples prepared by the solvothermal method is higher than that of the samples prepared by the solid-state reaction and flux method. The superconducting transition temperature (Tc) of FeSe1-xTex for x=0, 0.1, 0.2 samples is near 9.3 K, 12.4 K, and 13.9 K, respectively, which is a bit higher than that of bulk samples. The electronic structures of these samples are investigated by X-ray photoemission spectroscopy and X-ray absorption spectroscopy. The Fe 2p X-ray photoemission spectroscopy spectra shift to higher binding energy by Te doping due to the increase in hole densities. X-ray photoemission spectroscopy spectra of Se 3d and Te 3d shift to higher binding energy and lower binding energy, respectively, resulting from the charge transfer between Se and Te. It is suggested that the hybridization between Fe 3d and Se 4p is strengthened. Our results imply that the hybridization between Fe 3d and Se 4p probably plays an important role in superconductivity.","PeriodicalId":7164,"journal":{"name":"Acta Physica Polonica A","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136055194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-01DOI: 10.12693/aphyspola.144.242
B. Turko, V. Vasil'ev, B. Sadovyi, V. Kapustianyk, Y. Eliyashevskyi, R. Serkiz
A photovoltaic cell based on p-GaN film/n-ZnO microrods quasi-array heterojunction was fabricated and investigated for the first time for harvesting energy from a near-ultraviolet source (395–400 nm). The source was a commercially available indoor light-emitting diode. According to the scanning electron microscopy data, the ZnO array consisted of tightly packed vertical microrods with a diameter of approximately 2–3 µm. The turn-on voltage of the heterojunction of ZnO/GaN (rods/film) was around 0.6 V. The diode-ideality factor was estimated to be of around 4. The current–voltage characteristic of the photovoltaic cell under near-ultraviolet illumination showed an open-circuit voltage of 0.26 V, a short-circuit current of 0.124 nA, and a fill factor of 39%, resulting in an overall efficiency of 1.4 x 10-5%. These results may be useful in the engineering of electronic devices based on the materials with optical transparency.
{"title":"Photovoltaic Cell Based on n-ZnO Microrods and p-GaN Film","authors":"B. Turko, V. Vasil'ev, B. Sadovyi, V. Kapustianyk, Y. Eliyashevskyi, R. Serkiz","doi":"10.12693/aphyspola.144.242","DOIUrl":"https://doi.org/10.12693/aphyspola.144.242","url":null,"abstract":"A photovoltaic cell based on p-GaN film/n-ZnO microrods quasi-array heterojunction was fabricated and investigated for the first time for harvesting energy from a near-ultraviolet source (395–400 nm). The source was a commercially available indoor light-emitting diode. According to the scanning electron microscopy data, the ZnO array consisted of tightly packed vertical microrods with a diameter of approximately 2–3 µm. The turn-on voltage of the heterojunction of ZnO/GaN (rods/film) was around 0.6 V. The diode-ideality factor was estimated to be of around 4. The current–voltage characteristic of the photovoltaic cell under near-ultraviolet illumination showed an open-circuit voltage of 0.26 V, a short-circuit current of 0.124 nA, and a fill factor of 39%, resulting in an overall efficiency of 1.4 x 10-5%. These results may be useful in the engineering of electronic devices based on the materials with optical transparency.","PeriodicalId":7164,"journal":{"name":"Acta Physica Polonica A","volume":"87 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136055211","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-01DOI: 10.12693/aphyspola.144.263
O. Bezkrovna, P. Zdeb, O. Bezkrovnyi, R. Lisiecki, P.J. Dereń
The effect of dopants (Nd3+, Pr3+) introduced into micro and nanocrystals of LuPO4 on their structural, morphological, and luminescent properties has been examined. The tetragonal structure of the synthesized phosphates was confirmed by means of an X-ray diffraction study. Transmission electron microscopy of LuPO4 samples doped with 0–2% Pr3+ and 0–3% Nd3+ obtained by the microwave hydrothermal method showed the formation of the nanocrystalline samples with a size of 40–90 nm. Spectroscopic study of Lu1-x-yPrxNdyPO4 micro and nanocrystals showed that effective energy transfer occurs between the selected optically active ions. Due to significant ion–ion interactions in the co-doped orthophosphates, the contribution of nonradiative processes to the relaxation of the luminescent levels of praseodymium and neodymium effectively increases. The energy transfer in the micro and nanocrystals Lu1-x-yPrxNdyPO4 from Pr3+ ions to Nd3+ ions results in the efficient near-infrared emission in the region of the spectrum between 1064 and 1350 nm, whereas for Lu1-x-yPrxNdyPO4 nanocrystals doped with Pr3+ and Nd3+ ions, a particularly intense Nd3+ luminescence appears at 1064 nm. There is a significant impact of concentration of the Pr3+ and Nd3+ ions on near-infrared luminescence intensity of the studied Lu1-x-yPrxNdyPO4 phosphates. The relaxation dynamic of the neodymium metastable excited state is substantially sensitive to a variety of praseodymium admixtures, and inversely, the experimental lifetime of 1D2 Pr3+ emission level gradually decreases with increasing Nd3+ concentration.
{"title":"Micro and Nanocrystalline LuPO<sub>4</sub>(Ln<sup>3+</sup>: Nd, Pr) - Morphology, Luminescence and Inter-ionic Interplays","authors":"O. Bezkrovna, P. Zdeb, O. Bezkrovnyi, R. Lisiecki, P.J. Dereń","doi":"10.12693/aphyspola.144.263","DOIUrl":"https://doi.org/10.12693/aphyspola.144.263","url":null,"abstract":"The effect of dopants (Nd3+, Pr3+) introduced into micro and nanocrystals of LuPO4 on their structural, morphological, and luminescent properties has been examined. The tetragonal structure of the synthesized phosphates was confirmed by means of an X-ray diffraction study. Transmission electron microscopy of LuPO4 samples doped with 0–2% Pr3+ and 0–3% Nd3+ obtained by the microwave hydrothermal method showed the formation of the nanocrystalline samples with a size of 40–90 nm. Spectroscopic study of Lu1-x-yPrxNdyPO4 micro and nanocrystals showed that effective energy transfer occurs between the selected optically active ions. Due to significant ion–ion interactions in the co-doped orthophosphates, the contribution of nonradiative processes to the relaxation of the luminescent levels of praseodymium and neodymium effectively increases. The energy transfer in the micro and nanocrystals Lu1-x-yPrxNdyPO4 from Pr3+ ions to Nd3+ ions results in the efficient near-infrared emission in the region of the spectrum between 1064 and 1350 nm, whereas for Lu1-x-yPrxNdyPO4 nanocrystals doped with Pr3+ and Nd3+ ions, a particularly intense Nd3+ luminescence appears at 1064 nm. There is a significant impact of concentration of the Pr3+ and Nd3+ ions on near-infrared luminescence intensity of the studied Lu1-x-yPrxNdyPO4 phosphates. The relaxation dynamic of the neodymium metastable excited state is substantially sensitive to a variety of praseodymium admixtures, and inversely, the experimental lifetime of 1D2 Pr3+ emission level gradually decreases with increasing Nd3+ concentration.","PeriodicalId":7164,"journal":{"name":"Acta Physica Polonica A","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136055081","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-01DOI: 10.12693/aphyspola.144.234
I.A. Sadiq, M.A.Z. Habeeb
Bose–Einstein condensation, as a fifth state of matter, can only occur under certain conditions. One of those conditions is the spatial dimensions confining the bosonic systems. We investigated Bose–Einstein condensation for a finite number of harmonically trapped bosons on fractal structures. The investigation involves two approaches; one belongs to standard Bose–Einstein statistics, and the other belongs to the theory of q-deformed bosons. The properties of Bose–Einstein condensates in the two approaches are computed by performing the sum over the energy states. From these two approaches, we attempt to gain insight into the possibility of using q-numbers to assign fractal dimensions via Bose–Einstein condensation. In this endeavor, the bosons are considered ideal to emphasize that the parameter q only represents the fractal dimension of the structures confining the bosons. The results reveal that a condensate of q-deformed bosons with q=0.74 is adequate to represent a condensate of standard bosons on a Sierpiński carpet. The results also reveal that a condensate of q-deformed bosons with q=0.33 is adequate to represent a condensate of standard bosons on a Menger sponge. We also suggest an expression for using the parameter q to measure the interaction between bosons harmonically trapped on fractal structures, which may also help to study the effect of porosity or fractal dimension on the interaction between bosons.
{"title":"Bose-Einstein Condensation of q-Deformed Bosons Harmonically Trapped on Sierpiński Carpet and Menger Sponge","authors":"I.A. Sadiq, M.A.Z. Habeeb","doi":"10.12693/aphyspola.144.234","DOIUrl":"https://doi.org/10.12693/aphyspola.144.234","url":null,"abstract":"Bose–Einstein condensation, as a fifth state of matter, can only occur under certain conditions. One of those conditions is the spatial dimensions confining the bosonic systems. We investigated Bose–Einstein condensation for a finite number of harmonically trapped bosons on fractal structures. The investigation involves two approaches; one belongs to standard Bose–Einstein statistics, and the other belongs to the theory of q-deformed bosons. The properties of Bose–Einstein condensates in the two approaches are computed by performing the sum over the energy states. From these two approaches, we attempt to gain insight into the possibility of using q-numbers to assign fractal dimensions via Bose–Einstein condensation. In this endeavor, the bosons are considered ideal to emphasize that the parameter q only represents the fractal dimension of the structures confining the bosons. The results reveal that a condensate of q-deformed bosons with q=0.74 is adequate to represent a condensate of standard bosons on a Sierpiński carpet. The results also reveal that a condensate of q-deformed bosons with q=0.33 is adequate to represent a condensate of standard bosons on a Menger sponge. We also suggest an expression for using the parameter q to measure the interaction between bosons harmonically trapped on fractal structures, which may also help to study the effect of porosity or fractal dimension on the interaction between bosons.","PeriodicalId":7164,"journal":{"name":"Acta Physica Polonica A","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136055193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-01DOI: 10.12693/aphyspola.144.209
Y.M. Sun, P.L. Zhang
Fe40Co40Zr7V2B11-xTax (x=0, 1, 2) alloy ribbons are prepared through single-roller melt spinning followed by annealing in a temperature range of 300–700°C. The influence of substituting Ta for V on the free and wheel surface structures of the samples is investigated. The addition of Ta improves the glass-formation ability owing to the large atomic radius of Ta atoms. The as-quenched Fe40Co40Zr7V2B11 alloy is not amorphous, and α-Fe crystals are textured (200) on the free surface. Moreover, the as-quenched Fe40Co40Zr7V2B10Ta1 alloy is not completely amorphous, and a small amount of α-Fe crystals remains textured (200) on the free surface. The crystallization of the free surfaces of the Fe40Co40Zr7V2B11 and Fe40Co40Zr7V2B10Ta1 alloys differs from those of the wheel-contacted surfaces. Both the free and wheel-contacted surfaces of the as-quenched Fe40Co40Zr7V2B9Ta2 alloy exhibit fully amorphous structures. The crystallization of the free surface of the Fe40Co40Zr7V2B9Ta2 alloy is similar to that of the wheel-contacted surface. The ductility of the Fe40Co40Zr7V2B9Ta2 alloy is greater than that of the Fe40Co40Zr7V2B11 and Fe40Co40Zr7V2B10Ta1 alloys. The addition of Ta significantly improves the glass-forming ability and ductility of the alloy.
{"title":"Effect of Ta Addition on Glass-Forming Ability and Structures of Fe<sub>40</sub>Co<sub>40</sub>Zr<sub>7</sub>V<sub>2</sub>B<sub>11</sub> Alloy","authors":"Y.M. Sun, P.L. Zhang","doi":"10.12693/aphyspola.144.209","DOIUrl":"https://doi.org/10.12693/aphyspola.144.209","url":null,"abstract":"Fe40Co40Zr7V2B11-xTax (x=0, 1, 2) alloy ribbons are prepared through single-roller melt spinning followed by annealing in a temperature range of 300–700°C. The influence of substituting Ta for V on the free and wheel surface structures of the samples is investigated. The addition of Ta improves the glass-formation ability owing to the large atomic radius of Ta atoms. The as-quenched Fe40Co40Zr7V2B11 alloy is not amorphous, and α-Fe crystals are textured (200) on the free surface. Moreover, the as-quenched Fe40Co40Zr7V2B10Ta1 alloy is not completely amorphous, and a small amount of α-Fe crystals remains textured (200) on the free surface. The crystallization of the free surfaces of the Fe40Co40Zr7V2B11 and Fe40Co40Zr7V2B10Ta1 alloys differs from those of the wheel-contacted surfaces. Both the free and wheel-contacted surfaces of the as-quenched Fe40Co40Zr7V2B9Ta2 alloy exhibit fully amorphous structures. The crystallization of the free surface of the Fe40Co40Zr7V2B9Ta2 alloy is similar to that of the wheel-contacted surface. The ductility of the Fe40Co40Zr7V2B9Ta2 alloy is greater than that of the Fe40Co40Zr7V2B11 and Fe40Co40Zr7V2B10Ta1 alloys. The addition of Ta significantly improves the glass-forming ability and ductility of the alloy.","PeriodicalId":7164,"journal":{"name":"Acta Physica Polonica A","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136055196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-01DOI: 10.12693/aphyspola.144.214
M. Balvasi, A. Avazpour, J. Jalilian, M.Z. Bidsardare
We investigated the effects of the strain, edges, and width of penta-graphene nanoribbons on their electronic structure and transport properties using tight-binding approximation. We considered three different geometries of penta-graphene nanoribbons. In the first case, both the upper and lower edges have a zigzag shape. In the second case, the upper edge has a zigzag pattern, and the lower edge has a beard shape. In the third case, both the upper and lower edges are considered to be beard-shaped. The hopping parameters were evaluated based on Slater–Koster integrals. The Slater–Koster coefficients were evaluated using the TBStudio software package. In our model, we do not apply arbitrary amounts of strain to the structure. For the stability of the structure, we chose the allowable amounts of strain by using the calculated strain–stress curve. Based on the tight-binding approximation, the magnitude of the bandgap in each type of penta-graphene nanoribbon is reduced as the applied strain increases. In addition, the band structures of the three geometries changed, and the bandgap decreased with an increase in width. Hence, such configurations of penta-graphene nanoribbons are expected to be widely used in nano-electronic devices. Finally, we investigated transport properties using a tight-binding model and a generalized Green's function method in the Landauer–Buttiker formalism. By tuning the width of the penta-graphene nanoribbons and applying strain, the maximum current and a lower threshold voltage are achieved. With an increase in the width of the nanoribbon, the intensity of the current and the available energy levels have increased. Our calculated results may suggest potential applications of penta-graphene nanoribbons in spin electronics, nano-electronic devices, and solar cells. In addition, we provide theoretical guidance for regulating the properties of penta-graphene nanoribbons by applying strain, edge modifications, and different widths.
{"title":"Tuning the Electronic and Transport Properties of Three Configurations of Penta-Graphene Nanoribbons","authors":"M. Balvasi, A. Avazpour, J. Jalilian, M.Z. Bidsardare","doi":"10.12693/aphyspola.144.214","DOIUrl":"https://doi.org/10.12693/aphyspola.144.214","url":null,"abstract":"We investigated the effects of the strain, edges, and width of penta-graphene nanoribbons on their electronic structure and transport properties using tight-binding approximation. We considered three different geometries of penta-graphene nanoribbons. In the first case, both the upper and lower edges have a zigzag shape. In the second case, the upper edge has a zigzag pattern, and the lower edge has a beard shape. In the third case, both the upper and lower edges are considered to be beard-shaped. The hopping parameters were evaluated based on Slater–Koster integrals. The Slater–Koster coefficients were evaluated using the TBStudio software package. In our model, we do not apply arbitrary amounts of strain to the structure. For the stability of the structure, we chose the allowable amounts of strain by using the calculated strain–stress curve. Based on the tight-binding approximation, the magnitude of the bandgap in each type of penta-graphene nanoribbon is reduced as the applied strain increases. In addition, the band structures of the three geometries changed, and the bandgap decreased with an increase in width. Hence, such configurations of penta-graphene nanoribbons are expected to be widely used in nano-electronic devices. Finally, we investigated transport properties using a tight-binding model and a generalized Green's function method in the Landauer–Buttiker formalism. By tuning the width of the penta-graphene nanoribbons and applying strain, the maximum current and a lower threshold voltage are achieved. With an increase in the width of the nanoribbon, the intensity of the current and the available energy levels have increased. Our calculated results may suggest potential applications of penta-graphene nanoribbons in spin electronics, nano-electronic devices, and solar cells. In addition, we provide theoretical guidance for regulating the properties of penta-graphene nanoribbons by applying strain, edge modifications, and different widths.","PeriodicalId":7164,"journal":{"name":"Acta Physica Polonica A","volume":"121 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136054360","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-01DOI: 10.12693/aphyspola.144.226
P. Kumar, C. Tiwari
A study of the wakefield excitation in a magnetized quantum plasma is presented. The high-density plasma has been magnetized through a magnetic field applied in the longitudinal direction. Using a recently developed quantum hydrodynamic model and a perturbative technique, taking into account the quantum effects of Fermi pressure and Bohm potential, electric and magnetic wakefields were obtained for the Gaussian profile of the electromagnetic pulse. Electrons are trapped in the wakefields and accelerated to extremely high energies. It is observed that the quantum effects significantly affect the wakefield excitation. Quantum dispersive effects tend to reduce the acceleration gradient, whereas the external magnetic field helps with self-focusing and also contributes to acceleration. The axial and radial forces acting on a test electron have been calculated.
{"title":"Wakefield Excitation in Magnetized Quantum Plasma","authors":"P. Kumar, C. Tiwari","doi":"10.12693/aphyspola.144.226","DOIUrl":"https://doi.org/10.12693/aphyspola.144.226","url":null,"abstract":"A study of the wakefield excitation in a magnetized quantum plasma is presented. The high-density plasma has been magnetized through a magnetic field applied in the longitudinal direction. Using a recently developed quantum hydrodynamic model and a perturbative technique, taking into account the quantum effects of Fermi pressure and Bohm potential, electric and magnetic wakefields were obtained for the Gaussian profile of the electromagnetic pulse. Electrons are trapped in the wakefields and accelerated to extremely high energies. It is observed that the quantum effects significantly affect the wakefield excitation. Quantum dispersive effects tend to reduce the acceleration gradient, whereas the external magnetic field helps with self-focusing and also contributes to acceleration. The axial and radial forces acting on a test electron have been calculated.","PeriodicalId":7164,"journal":{"name":"Acta Physica Polonica A","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136055199","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-01DOI: 10.12693/aphyspola.144.255
H. Hakim, A.N. Mohammed, M.S. Hashim
The rapid breakdown anodizing method was used to produce (Bi, Bi2O3), (Pb, PbO2), and WO3 nanoparticles. These particles are utilized to fabricate gamma-ray shielding. The X-ray diffraction test displayed polycrystalline structures for all samples. Scanning electron microscope images illustrated the formation of (Bi, Bi2O3) and (Pb, PbO2) nanoplates and WO3 semi-sphere particles. Pressures of 318, 477, and 636 MPa were applied to reduce vacancies within the prepared powders and increase their densities. Cylindrical samples with a diameter of 14 mm and different thicknesses were formed. Utilizing gamma rays produced by sources like Am-241 (59.54 keV), Cs-137 (661.6 keV), Co-60 (1173 keV), and Co-60 (1332 keV), the shielding characteristics of the manufactured samples were studied. The linear attenuation coefficient, mass attenuation coefficient, and half-value layer were determined after the gamma flux was measured using a NaI(Tl) detector. The two attenuation coefficients were functions of the source energy, and they had the highest values for (Pb, PbO2) and the lowest for the WO3 sample. The atomic numbers of the elements used and the size of the voids inside the prepared powders played the greatest role in determining the values of the shielding parameters.
{"title":"Fabrication of Gamma-Ray Shielding Using Rapid Breakdown Anodization","authors":"H. Hakim, A.N. Mohammed, M.S. Hashim","doi":"10.12693/aphyspola.144.255","DOIUrl":"https://doi.org/10.12693/aphyspola.144.255","url":null,"abstract":"The rapid breakdown anodizing method was used to produce (Bi, Bi2O3), (Pb, PbO2), and WO3 nanoparticles. These particles are utilized to fabricate gamma-ray shielding. The X-ray diffraction test displayed polycrystalline structures for all samples. Scanning electron microscope images illustrated the formation of (Bi, Bi2O3) and (Pb, PbO2) nanoplates and WO3 semi-sphere particles. Pressures of 318, 477, and 636 MPa were applied to reduce vacancies within the prepared powders and increase their densities. Cylindrical samples with a diameter of 14 mm and different thicknesses were formed. Utilizing gamma rays produced by sources like Am-241 (59.54 keV), Cs-137 (661.6 keV), Co-60 (1173 keV), and Co-60 (1332 keV), the shielding characteristics of the manufactured samples were studied. The linear attenuation coefficient, mass attenuation coefficient, and half-value layer were determined after the gamma flux was measured using a NaI(Tl) detector. The two attenuation coefficients were functions of the source energy, and they had the highest values for (Pb, PbO2) and the lowest for the WO3 sample. The atomic numbers of the elements used and the size of the voids inside the prepared powders played the greatest role in determining the values of the shielding parameters.","PeriodicalId":7164,"journal":{"name":"Acta Physica Polonica A","volume":"131 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136054370","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-01DOI: 10.12693/aphyspola.144.173
X. Xie, Q. Wei, X. Jia, Z. Wu, M. Zhang
Using the structure search method combined with first-principles calculations, a new silicon allotrope with cubic symmetry, c -Si16, is proposed. To examine the stability of c -Si16 under ambient pressure, systematic calculations of its structural, mechanical, and electronic properties were performed. Mechanical and dynamic stability are demonstrated by elastic constants and phonon spectra, respectively. In addition, the band structure and density of states show that c -Si16 is a metallic silicon material, and its conductivity mainly comes from the p -orbital electrons of silicon.
{"title":"A New Metallic Silicon Allotrope: c-Si16","authors":"X. Xie, Q. Wei, X. Jia, Z. Wu, M. Zhang","doi":"10.12693/aphyspola.144.173","DOIUrl":"https://doi.org/10.12693/aphyspola.144.173","url":null,"abstract":"Using the structure search method combined with first-principles calculations, a new silicon allotrope with cubic symmetry, c -Si16, is proposed. To examine the stability of c -Si16 under ambient pressure, systematic calculations of its structural, mechanical, and electronic properties were performed. Mechanical and dynamic stability are demonstrated by elastic constants and phonon spectra, respectively. In addition, the band structure and density of states show that c -Si16 is a metallic silicon material, and its conductivity mainly comes from the p -orbital electrons of silicon.","PeriodicalId":7164,"journal":{"name":"Acta Physica Polonica A","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135686639","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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