Physics Open最新文献

{"title":"Design of conformal dual stop band frequency selective surface for microwave applications","authors":"Naveena Meka,&nbsp;Krishnan Shambavi","doi":"10.1016/j.physo.2025.100352","DOIUrl":"10.1016/j.physo.2025.100352","url":null,"abstract":"<div><div>A Conformal single layer ultra-thin dual band stop and bandpass Frequency Selective Surface (FSS) for microwave applications is proposed and experimentally evaluated in this letter. The proposed FSS uniquely combines dual passband functionality allowing the lower and upper WLAN spectra—with dual stopband performance that delivers wideband, wide-angle, and polarization-independent shielding for TE and TM polarizations. The proposed FSS consists of two Concentric Square Rings (CCSR) and two Convoluted Square Rings (CVSR) on a Rogers 3010 substrate of relative permittivity 10.2 and thickness 0.25 mm. The dimension of the unit cell is 0.1123<em>λo</em> × 0.1123<em>λo, λo</em> is the lowest resonant frequency. Planar and conformal FSS structures were systematically analyzed, fabricated, and characterized in an anechoic chamber to evaluate their passband performance and shielding effectiveness. The proposed FSS exhibits dual wide stopband characteristics ranging from 1.05 to 1.75 GHz, 3.4–4.6 GHz with shield effectiveness of 51 dB and 45 dB at 1.4 GHz, 4.06 GHz respectively. It also exhibits dual pass band response from 2.2 to 2.5 GHz and 5.4–5.9 GHz within band with insertion loss of 0.8 dB and 0.5 dB respectively. It also exhibits outstanding angular and polarization stability up to 80°. The close correlation between simulated and measured transmission responses validates the design's effectiveness in shielding the L band and 5G NR spectrum while maintaining high transmission in the lower and upper WLAN frequency bands.</div></div>","PeriodicalId":36067,"journal":{"name":"Physics Open","volume":"26 ","pages":"Article 100352"},"PeriodicalIF":1.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145624952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimizing light guide shape of beta-ray detector for surface contamination monitor","authors":"Makoto Sasano ,&nbsp;Yusuke Niwa ,&nbsp;Tetsushi Azuma ,&nbsp;Masateru Hayashi","doi":"10.1016/j.physo.2026.100372","DOIUrl":"10.1016/j.physo.2026.100372","url":null,"abstract":"<div><div>Object surface must be inspected for possible radioactive contamination when objects are moved from nuclear facilities and decommissioning sites. Currently, large vehicles are manually inspected for contamination. To avoid exposing the inspection workers to radiation, an automatic contamination inspection instrument for large vehicles should be developed. Moreover, such an instrument will require a compact and light detect.</div><div>The light guide of the detector should be designed that can make the detector compact and sensitive enough. <u>We used a 150 <u>×</u> 150 <u>×</u> 0.5 mm</u>³ <u>plastic scintillator for our developing monitor.</u> In particular, the size of the light guide should be optimized before producing the detector, and here, Geant4, a radiation simulation including optical processes, can be used for determining a suitable light guide size. In this study, the light collection efficiency, the instrument efficiency, and uniformity were estimated with Geant4. Based on the estimations, we found the optimal light-guide height and photodetector window size to be 40 mm and 20 mm, respectively, for a scintillator <u>of 150 <u>×</u> 150 <u>×</u> 0.5 mm</u>³. We fabricated a detector incorporating the optimized light guide and examined its performance in an experiment with radioactive sources ¹³⁷Cs and ⁶⁰Co. The measures of instrument efficiency and uniformity were consistent with those predicted by the simulation. If this detector were installed in the instrument, it would be able to inspect a large vehicle in 250 s <u>under a gamma-ray background of 1.0 μSv/h</u>.</div></div>","PeriodicalId":36067,"journal":{"name":"Physics Open","volume":"26 ","pages":"Article 100372"},"PeriodicalIF":1.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147395003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mid-infrared filters based on subwavelength grating structures supporting high-Q resonance modes","authors":"Yuanhang Zhao ,&nbsp;Zhihui Wei ,&nbsp;Kai Wang ,&nbsp;Bo Wang ,&nbsp;Guiyan zhao ,&nbsp;Yan Wang","doi":"10.1016/j.physo.2025.100366","DOIUrl":"10.1016/j.physo.2025.100366","url":null,"abstract":"<div><div>We propose a notch filter based on a subwavelength grating structure, featuring ultra-narrowband suppression characteristics within the mid-infrared spectrum (3–5 μm). The device leverages Fano resonance generated by the coupling between Fabry–Pérot cavity modes and surface plasmon polaritons. By introducing controlled nanoscale perturbations within the unit cell, a high-<em>Q</em> resonant state is excited, resulting in a narrow linewidth of 1.08 nm in the transmission spectrum. The resonance depth can be freely adjusted via the grating duty cycle, while the quality factor increases with the degree of asymmetry, reaching up to 3900. The structure also exhibits a strong response to variations in the ambient refractive index while maintaining a high quality factor (&gt;800), and demonstrates a high sensing sensitivity of 798 nm/RIU. This work establishes a versatile and robust platform for high-performance mid-infrared filtering and sensing applications, including refractive index detection, molecular spectroscopy, thermal imaging, and gas sensing.</div></div>","PeriodicalId":36067,"journal":{"name":"Physics Open","volume":"26 ","pages":"Article 100366"},"PeriodicalIF":1.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145976809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spiral Compactification with torsion-monodromy locking","authors":"Matthew C. Allaby","doi":"10.1016/j.physo.2025.100364","DOIUrl":"10.1016/j.physo.2025.100364","url":null,"abstract":"<div><div>We present a unified geometric framework in which spiral compactification with torsion and monodromy locking defines a minimal invariant structure governing spectra, interactions, and stability in a five dimensional Kaluza–Klein type setting. The construction introduces a compact spiral dimension endowed with intrinsic torsion, where monodromy fixes allowed winding modes and removes ambiguities associated with conventional compactification schemes. A central result is the identification of a minimal invariant, <span><math><msub><mrow><mi>D</mi></mrow><mrow><mo>min</mo></mrow></msub></math></span>, which uniquely determines admissible field configurations, vertical mode spectra, and coupling structure across gravitational and gauge sectors.</div><div>Unlike standard approaches that rely on additional symmetry assumptions or external stabilization mechanisms, the present framework derives spectral discreteness and mode selection directly from geometric and topological constraints. We show that torsion and monodromy locking lead to robust quantization conditions, suppress pathological zero modes, and yield a constrained but flexible parameter space compatible with known four dimensional physics. To illustrate the formalism, we provide representative examples and limiting cases that connect the theory to familiar Kaluza–Klein models, as well as to torsion driven phenomena in cosmology and condensed matter systems.</div><div>These results establish a mathematically rigorous yet physically motivated foundation for unification based on spiral geometry. The framework is falsifiable in principle through its predicted mode structure and torsion induced spectral features, offering clear pathways toward phenomenological investigation in high energy physics, cosmology, and analog systems.</div></div>","PeriodicalId":36067,"journal":{"name":"Physics Open","volume":"26 ","pages":"Article 100364"},"PeriodicalIF":1.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145938850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Heat treatment-induced changes in structural and superconducting properties of (Y1−xSmx)1−yEuyBaSrCu3O6+z compounds","authors":"Fatima Bouzit ,&nbsp;Mohammed Bellioua ,&nbsp;Mohamed Id Elamel ,&nbsp;Mohammed Khenfouch ,&nbsp;Driss Soubane ,&nbsp;Mohamed Errai ,&nbsp;Ahmed Tirbiyine","doi":"10.1016/j.physo.2026.100379","DOIUrl":"10.1016/j.physo.2026.100379","url":null,"abstract":"<div><div>This study provides new experimental insights into the structural and superconducting properties of (Y_1−xSm_x)_1−yEu_yBaSrCu₃O_6+z compounds. The effects of two annealing procedures oxygen ([O]) and successive argon–oxygen ([AO]) treatments were systematically investigated for varying Sm and Eu contents. The AO treatment generally increases orthorhombicity and enhances the critical temperature (Tc) in Sm-substituted samples, whereas YBaSrCu₃O_6+z exhibits a slight reduction in Tc. These results emphasize the correlation between lattice parameter variations, oxygen ordering in the Cu(1)O plane, and superconducting properties. Overall, the findings extend previously reported trends relating structural parameters, oxygen order, and hole concentration to Tc to Sm and Eu substituted compositions.</div></div>","PeriodicalId":36067,"journal":{"name":"Physics Open","volume":"26 ","pages":"Article 100379"},"PeriodicalIF":1.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147395002","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lanthanum and Oxygen vacancy effect on the ground state properties of bulk La0.75Ca0.25MnO3: A DFT+U study","authors":"L. Mouketo ,&nbsp;D.P. Mankou Bakala ,&nbsp;J.F. Matoko Ngouma ,&nbsp;B.R. Malonda-Boungou ,&nbsp;D. Joubert ,&nbsp;B. M’Passi-Mabiala","doi":"10.1016/j.physo.2026.100377","DOIUrl":"10.1016/j.physo.2026.100377","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Structural, electronic and magnetic properties of stoichiometric, La- and O-deficient bulk &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;La&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;75&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;Ca&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;25&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;MnO&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;3&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; compounds have been studied within the spin polarized GGA+U approximation of density functional theory. La-deficient &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;La&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;75&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;Ca&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;25&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;MnO&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;3&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; exhibits an insulating G-type antiferromagnetic nature, and shows an energy gap of 0.655 eV. The O-vacancy &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;La&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;75&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;Ca&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;25&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;MnO&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;75&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; and &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;La&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;75&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;Ca&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;25&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;MnO&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;50&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; compounds show a ferromagnetic and A-type antiferromagnetic metallic behavior, respectively with an increased on-site Mn magnetic moment. Projected density of states show a more occupation of &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;e&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;g&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; orbitals for La&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;75&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;Ca&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;25&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;MnO&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;75&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; and La&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;75&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;Ca&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;25&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;MnO&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;5&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;, suggesting existence of Mn&lt;span&gt;&lt;math&gt;&lt;msup&gt;&lt;mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;mo&gt;+&lt;/mo&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/math&gt;&lt;/span&gt; along with Mn&lt;span&gt;&lt;math&gt;&lt;msup&gt;&lt;mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;3&lt;/mn&gt;&lt;mo&gt;+&lt;/mo&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/math&gt;&lt;/span&gt; and Mn&lt;span&gt;&lt;math&gt;&lt;msup&gt;&lt;mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;4&lt;/mn&gt;&lt;mo&gt;+&lt;/mo&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/math&gt;&lt;/span&gt;. &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;e&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;g&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; orbitals are almost fully unoccupied, suggesting the dominant presence of Mn&lt;span&gt;&lt;math&gt;&lt;msup&gt;&lt;mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;4&lt;/mn&gt;&lt;mo&gt;+&lt;/mo&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/math&gt;&lt;/span&gt; in &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;La&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;5&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;Ca&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;25&lt;/mn&gt;&lt;/mrow&gt;&lt;/msu","PeriodicalId":36067,"journal":{"name":"Physics Open","volume":"26 ","pages":"Article 100377"},"PeriodicalIF":1.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147395015","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Non-exponential current decay in first-order circuits with finite time constants","authors":"Vladimir Ivchenko","doi":"10.1016/j.physo.2026.100383","DOIUrl":"10.1016/j.physo.2026.100383","url":null,"abstract":"<div><div>We present a theoretical framework, derived from Maxwell’s equations for conducting media, to describe transient current decay in circuits with finite time constants. The temporal behaviour of the current is shown to be governed by a single dimensionless parameter <span><math><mi>β</mi></math></span>, defined as the ratio of the circuit time constant to the magnetic diffusion time. For finite values of <span><math><mi>β</mi></math></span>, numerical solutions of the resulting Volterra equation show a systematic deviation from the conventional exponential decay predicted by the lumped-element model. In RC circuits, the model predicts a crossover from monotonic decay to damped oscillatory behaviour below a critical value <span><math><mrow><msub><mrow><mi>β</mi></mrow><mrow><mi>cr</mi></mrow></msub><mo>≈</mo><mn>0</mn><mo>.</mo><mn>4</mn></mrow></math></span>, as obtained numerically and supported by a controlled single-mode approximation. The number of such oscillations is finite, and they turn out to be irregular on the time scale. As the <span><math><mi>β</mi></math></span>-parameter decreases, this number increases. A simple physical interpretation of these results is also provided.</div></div>","PeriodicalId":36067,"journal":{"name":"Physics Open","volume":"26 ","pages":"Article 100383"},"PeriodicalIF":1.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147395018","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of thermo-magnetic properties in Ni-nanoparticles and Ni-PVA composites","authors":"Mahmoud A. Hamad ,&nbsp;Hatem R. Alamri ,&nbsp;Ashraf M. Mohamed ,&nbsp;Yasser I. Khedr ,&nbsp;Mohamed E. Harb ,&nbsp;Sameh M. Elghnam","doi":"10.1016/j.physo.2026.100368","DOIUrl":"10.1016/j.physo.2026.100368","url":null,"abstract":"<div><div>To simulate the magnetocaloric effect (MCE) of Ni-nanoparticles and Ni-PVA composites, a phenomenological model (PM) is used. The MCE parameters of Ni-nanoparticles and Ni-PVA composites are calculated as the results of magnetization vs. temperature simulations. The cryogenic temperature range of MCE in Ni-nanoparticles and Ni-PVA composites is 10–40 K. Furthermore, Ni-nanoparticles serve important roles in tailoring the specific heat variability and changing the temperature range that covers this variation. In comparison, the MCE parameters of Ni-nanoparticles and Ni-PVA composites are therefore larger than the various MCE parameters of some published magnetocaloric (MC) samples. It is stated that Ni-nanoparticles and Ni-PVA composites could be utilized in effective cryogenic MR as MC magnets.</div></div>","PeriodicalId":36067,"journal":{"name":"Physics Open","volume":"26 ","pages":"Article 100368"},"PeriodicalIF":1.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145938853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Machine learning Calabi–Yau three-folds, four-folds, and five-folds","authors":"Kaniba Mady Keita ,&nbsp;Younouss Hamèye Dicko","doi":"10.1016/j.physo.2025.100360","DOIUrl":"10.1016/j.physo.2025.100360","url":null,"abstract":"<div><div>In this manuscript, we demonstrate, using several regression techniques, that the remaining independent Hodge numbers of complete intersection Calabi–Yau four-folds and five-folds can be machine learned from <span><math><msup><mrow><mi>h</mi></mrow><mrow><mn>1</mn><mo>,</mo><mn>1</mn></mrow></msup></math></span> and <span><math><msup><mrow><mi>h</mi></mrow><mrow><mn>2</mn><mo>,</mo><mn>1</mn></mrow></msup></math></span>. Consequently, we combine the Hodge numbers <span><math><msup><mrow><mi>h</mi></mrow><mrow><mn>1</mn><mo>,</mo><mn>1</mn></mrow></msup></math></span> and <span><math><msup><mrow><mi>h</mi></mrow><mrow><mn>2</mn><mo>,</mo><mn>1</mn></mrow></msup></math></span> from the complete intersection Calabi-Yau three-folds, four-folds, and five-folds into a single dataset. We then implement various classification algorithms on this dataset. For example, Gaussian process and naive Bayes classifiers both achieve 100% accuracy in binary classification between three-folds and four-folds. Using the Support Vector Machine (SVM) algorithm, a special corner is identified in the Calabi–Yau four-fold landscape (characterized by <span><math><mrow><mn>15</mn><mo>≤</mo><msup><mrow><mi>h</mi></mrow><mrow><mn>1</mn><mo>,</mo><mn>1</mn></mrow></msup><mo>≤</mo><mn>30</mn></mrow></math></span> and <span><math><mrow><mn>95</mn><mo>≤</mo><msup><mrow><mi>h</mi></mrow><mrow><mn>2</mn><mo>,</mo><mn>1</mn></mrow></msup><mo>≤</mo><mn>100</mn></mrow></math></span>) during multiclass classification. Furthermore, the highest accuracy 1.00000, in classifying Calabi–Yau three-folds, four-folds, and five-folds is obtained using the naive Bayes classifier.</div></div>","PeriodicalId":36067,"journal":{"name":"Physics Open","volume":"26 ","pages":"Article 100360"},"PeriodicalIF":1.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145797376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dosimetric and radiobiological parameters in brain cancers: A comparison of IMRT and VMAT techniques","authors":"Hamed Zamani ,&nbsp;Mohsen Saeb ,&nbsp;Shahram Monadi ,&nbsp;Mostafa Alizade-Harakiyan ,&nbsp;Ali Akhavan ,&nbsp;Amin Khodaei ,&nbsp;Alireza Farajollahi ,&nbsp;Mikaeil Molazadeh","doi":"10.1016/j.physo.2025.100362","DOIUrl":"10.1016/j.physo.2025.100362","url":null,"abstract":"<div><h3>Aim</h3><div>This study aimed to perform a physics-driven comparison of volumetric modulated arc therapy (VMAT) and intensity-modulated radiation therapy (IMRT) for brain cancers by integrating quantitative dosimetric indices derived from Monte Carlo–based dose calculation and radiobiological modeling. Plans prescribed at 50 Gy and 60 Gy were evaluated to investigate both physical dose distribution characteristics and predicted biological outcomes.</div></div><div><h3>Materials and methods</h3><div>Eighty-four computed tomography (CT) datasets of brain cancer patients (mean age, 51.9 ± 12.8 years) were used for treatment planning. IMRT plans were generated using 7–9 non-coplanar fields, while VMAT plans employed a single full clockwise arc. Dose calculations were performed using a Monte Carlo algorithm within the treatment planning system to ensure accurate modeling of dose deposition in heterogeneous intracranial tissues. Quantitative dosimetric parameters, including minimum, mean, maximum doses and dose–volume metrics, were extracted. Conformity index (CI) and homogeneity index (HI) were calculated to assess plan quality from a physics standpoint. For radiobiological evaluation, dose–volume histograms (DVHs) were exported to Biosuit software to compute tumor control probability (TCP) using Niemierko's EUD-based model and normal tissue complication probability (NTCP) for organs at risk (OARs) using the Lyman–Kutcher–Burman (LKB) model.</div></div><div><h3>Results</h3><div>VMAT demonstrated significantly shorter delivery times compared with IMRT (7.52 ± 0.60 vs. 11.20 ± 1.14 min; P = 0.012) and required fewer monitor units per fraction, reflecting higher delivery efficiency. Quantitative dosimetric analysis revealed significant differences in D_min, D2 %, HI (0.12 ± 0.07 for VMAT vs. 0.14 ± 0.08 for IMRT; P = 0.01), and CI (0.76 ± 0.05 for VMAT vs. 0.72 ± 0.05 for IMRT; P &lt; 0.001), indicating improved dose conformity and homogeneity with VMAT. Radiobiological modeling showed higher TCP for VMAT (0.83 ± 0.07 vs. 0.80 ± 0.06; P = 0.04) and generally lower NTCP and EUD values for several OARs, although most NTCP differences were not statistically significant. Lower prescription dose (50 Gy) resulted in reduced OAR doses and NTCP values compared with 60 Gy.</div></div><div><h3>Conclusion</h3><div>From a medical physics perspective, VMAT provides superior dosimetric performance and delivery efficiency compared with IMRT, while Monte Carlo–based dose calculation and radiobiological modeling suggest modest improvements in predicted tumor control and normal tissue sparing. The integration of advanced dose calculation algorithms with TCP/NTCP analysis enhances understanding of the physical–biological interplay in intracranial radiotherapy planning.</div></div>","PeriodicalId":36067,"journal":{"name":"Physics Open","volume":"26 ","pages":"Article 100362"},"PeriodicalIF":1.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145938933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}