Physica B-condensed Matter最新文献

{"title":"Tunable binding energy, stark shift and photoionization cross-section of 2D-hemicylindrical nanostructure under non-resonant laser and electric fields","authors":"S. Chouef ,&nbsp;M. Hbibi ,&nbsp;R. Boussetta ,&nbsp;A. El Moussaouy ,&nbsp;F. Falyouni ,&nbsp;O. Mommadi ,&nbsp;C.A. Duque","doi":"10.1016/j.physb.2025.418233","DOIUrl":"10.1016/j.physb.2025.418233","url":null,"abstract":"<div><div>This study investigates the impact of laser and electric fields on the electronic and optical properties of a 2D hemicylindrical quantum system. Using the effective mass approximation and solving the Schrödinger equation numerically via the finite element method, we analyze the Stark shift, binding energy, polarizability, and photoionization cross section under varying impurity positions and external field strengths. The results reveal that both fields significantly modify the confinement potential, leading to distinct nonlinear behaviors. The Stark shift exhibits a strong dependence on laser intensity, depending on the impurity localization, with a critical intersection point emerging under specific conditions. Similarly, the binding energy decreases as laser intensity increases, with critical field strengths influencing this trend. The polarizability displays strong field-dependent variations, transitioning from linear to nonlinear regimes. Additionally, the photoionization cross section undergoes a redshift with increasing laser intensity, while electric field effects enhance peak intensities due to Stark localization. These findings provide valuable insights into the tunability of quantum-confined systems, contributing to the design of advanced optoelectronic and quantum devices.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"726 ","pages":"Article 418233"},"PeriodicalIF":2.8,"publicationDate":"2025-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145940307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Tailoring nanocrystallite ZnS through Fe doping","authors":"Vigneshwari S R ,&nbsp;Dushyant Singh ,&nbsp;Tharundev VV ,&nbsp;Subha Maity ,&nbsp;Shivesh Yadav ,&nbsp;Krista R. Khiangte","doi":"10.1016/j.physb.2025.418216","DOIUrl":"10.1016/j.physb.2025.418216","url":null,"abstract":"<div><div>This study investigates the controlled tuning of structural, optical, and magnetic properties of zinc sulfide nanoparticles (NPs) through Fe doping to develop diluted magnetic semiconductors. Pristine and Fe-doped ZnS NPs were synthesized via a Sol–gel route by varying Fe/Zn ratios. XRD confirmed the retention of the zinc blende phase without secondary impurities, indicating successful Fe substitution. Microstructural analyses revealed polycrystalline NPs with increasing crystallite size while SEM–EDS verified Fe incorporation. Optical studies showed a slight band gap narrowing due to defect-induced states. Magnetic characterization revealed a transition from diamagnetism in pristine ZnS to mixed magnetic behavior upon Fe doping. The highest Fe-doped sample exhibited ferromagnetism, superparamagnetism, and a λ-like feature in temperature-dependent magnetization, confirming spin-glass behavior, along with an increased Curie temperature. Thus, Fe doping effectively tailors the optical and magnetic responses of ZnS, underscoring its potential for spintronic and multifunctional nanodevice applications.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"726 ","pages":"Article 418216"},"PeriodicalIF":2.8,"publicationDate":"2025-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145978665","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"A unified theoretical approach to size- and pressure-induced shifts in the melting temperature of metallic nanoparticles","authors":"Ravi Kumar ,&nbsp;Kuldeep Kholiya ,&nbsp;B.S. Tewari ,&nbsp;A. Dhyani","doi":"10.1016/j.physb.2025.418231","DOIUrl":"10.1016/j.physb.2025.418231","url":null,"abstract":"<div><div>In the present study, a theoretical model is developed to study the comparative effect of size and pressure on the melting temperature of metallic nano particles. For this purpose, basic thermal equation of state is employed and modified in the light of existing formalism to obtained desired equation for melting point as a function of both pressure and diameter of nanometals. The model is then used to numerically compute and analysed the melting curve of nano metals in the light of the dependency of pressure and size variations. For nano metals it is found that, the melting temperature increases with increase in pressure and size of the nanometals. It is interesting to note that the sharp decrease in melting temperature with decreasing particle size (below 5 nm) exhibits a nearly pressure-independent behavior. The results show strong agreement with existing theoretical and experimental data, confirming the validity of the model.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"726 ","pages":"Article 418231"},"PeriodicalIF":2.8,"publicationDate":"2025-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145940243","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Oxygen vacancy effects on the electronic and magnetic structure of La0.7Sr0.3MnO3 epitaxial thin films from first principles","authors":"Zachary Romestan ,&nbsp;Xu He ,&nbsp;A.C. Garcia-Castro ,&nbsp;Navid Mottaghi ,&nbsp;Mikel Holcomb ,&nbsp;Aldo H. Romero","doi":"10.1016/j.physb.2025.418229","DOIUrl":"10.1016/j.physb.2025.418229","url":null,"abstract":"<div><div>La_0.7Sr_0.3MnO<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> (LSMO) is a promising material for spintronic applications due to its robust ferromagnetism and complete spin polarization. The materials lose their properties when fabricated into thin films, which creates difficulties for their use in nanoscale device applications. The main factor behind this process is oxygen vacancies; yet, scientists face difficulties when trying to separate their individual effects through laboratory testing. In this work, we use first-principles calculations to investigate how oxygen vacancies affect the magnetic structure of LSMO thin films. Our results reveal that oxygen vacancies act as scattering centers and induce charge redistribution within the film, reducing oxidation states to between 2.8+ and 3.1+ in the thin films. The redistribution process causes ferromagnetic double exchange to lose its strength while superexchange interactions become stronger, resulting in local spin canting or flipping and a decrease in overall magnetization from 3.06 <span><math><msub><mrow><mi>μ</mi></mrow><mrow><mi>B</mi></mrow></msub></math></span>/Mn to 2.2 <span><math><msub><mrow><mi>μ</mi></mrow><mrow><mi>B</mi></mrow></msub></math></span>/Mn.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"726 ","pages":"Article 418229"},"PeriodicalIF":2.8,"publicationDate":"2025-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145940236","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Integrating machine learning and numerical modeling to predict bandgap and crystallite size of doped NiO for enhanced perovskite solar cells performance","authors":"Adil Alshoaibi ,&nbsp;Abdullahi Usman ,&nbsp;Eli Danladi ,&nbsp;Chawki Awada ,&nbsp;Shumaila Islam ,&nbsp;Fabian I. Ezema","doi":"10.1016/j.physb.2025.418220","DOIUrl":"10.1016/j.physb.2025.418220","url":null,"abstract":"<div><div>A modified NiO has emerged as a highly effective transport layer for both standard and inverted perovskite solar cells. The optimization of bandgap and crystallite thickness in doped NiO is crucial for improving device performance. In this study, machine learning predictive models were developed to estimate the bandgap and crystallite thickness of various doped NiO compositions using lattice parameters (<em>a</em> and <em>d</em>) and doping density as input features. The tree-based and ensemble models achieved the lowest, RMSE, and MAE, along with the highest R² values. The predicted bandgap and thickness values were further applied in simulating eighty ITO/ETL/C_SSnCl₆/PCBM/Se device configurations incorporating all doped NiO variants. The best-performing configuration for each ETL and doping density was identified, yielding thirteen optimized designs that outperformed reported counterparts. Among them, Li-doped NiO showed the highest performance, with the ITO/Li-NiO/CsSnCl₆/PCBM/Se device achieving a PCE of 23.764 %.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"725 ","pages":"Article 418220"},"PeriodicalIF":2.8,"publicationDate":"2025-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145885391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Resonance properties and phase transformations of the antiferromagnet YFe3(BO3)4","authors":"Aleksandr D. Prokhorov ,&nbsp;Roman Minikayev ,&nbsp;Jan Lančok ,&nbsp;Andrey Prokhorov","doi":"10.1016/j.physb.2025.418215","DOIUrl":"10.1016/j.physb.2025.418215","url":null,"abstract":"<div><div>This study presents the results of an investigation into the resonance properties of YFe₃(BO₃)₄ over a wide temperature range. In the paramagnetic phase, a single exchange-narrowed electron paramagnetic resonance (EPR) line with Lorentzian shape is observed. The anisotropy of the linewidth and the <em>g</em>-factor is attributed to the influence of the crystal field. Near the phase transition, a pronounced broadening and shift of the EPR line occurs. Below 10 K, in the antiferromagnetic phase, EPR signals of Fe³⁺ ions substituting yttrium and not interacting with the magnetically ordered sublattice are detected. In the diamagnetic analogs YAl₃(BO₃)₄ and YGa₃(BO₃)₄ doped with iron, EPR spectra of Fe³⁺ ions occupying sites with <em>D</em>_<em>3</em> symmetry were also detected, and the spin Hamiltonian parameters describing their properties were determined<strong>.</strong></div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"726 ","pages":"Article 418215"},"PeriodicalIF":2.8,"publicationDate":"2025-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145886407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Temperature-induced orbital-selective electronic transitions and dynamics valence fluctuations in γ-U3O8 revealed via many-body calculations","authors":"Ru-song Li ,&nbsp;Xin Qu ,&nbsp;Xiao-hua Zhou ,&nbsp;Jin-tao Wang ,&nbsp;Fei Wang ,&nbsp;Zheng Xie","doi":"10.1016/j.physb.2025.418223","DOIUrl":"10.1016/j.physb.2025.418223","url":null,"abstract":"<div><div>This study employs advanced density functional theory + dynamical mean-field theory (DFT + DMFT) to unravel the temperature-dependent electronic structure of high-pressure γ-U₃O₈. Our computations reveal a persistent orbital-selective electronic transition up to 1200 K, where spin-orbit coupling (SOC) drives a fundamental dichotomy, namely, the <em>j</em> = 5/2 manifold maintains metallic coherence with renormalized quasiparticles (<em>Z</em> = 0.339–0.362), while the <em>j</em> = 7/2 states exhibit robust insulating characteristics protected by an enhanced orbital anisotropy. The SOC-induced splitting generates distinct quasiparticle multiplets near the Fermi level. Temperature evolution demonstrates systematic enhancement of total 5<em>f</em> occupancy (<em>n</em>_5<em>f</em> = 2.581–2.624) and thermal redistribution among 5<em>f</em>^<em>n</em> configurations, dominated by 5<em>f</em>² and 5<em>f</em>³ states. This orbital polarization remains temperature-independent, indicating a many-body protection mechanism against the interband scattering. These findings establish γ-U₃O₈ as a paradigm material for exploring relativistic correlation physics in <em>f</em>-electron systems.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"725 ","pages":"Article 418223"},"PeriodicalIF":2.8,"publicationDate":"2025-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145885393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"The research of damage threshold of Pt film under irradiation by X-ray based on theoretical simulation","authors":"Tingting Sui,&nbsp;Haohui Zhuo,&nbsp;Xin Ju","doi":"10.1016/j.physb.2025.418227","DOIUrl":"10.1016/j.physb.2025.418227","url":null,"abstract":"<div><div>Platinum (Pt) plays a crucial role in the optical components of X-ray free-electron laser (XFEL) facilities as a thin-film material for reflectors. It is preferred to be damaged under high-energy X-ray irradiation. In this work, theoretical simulations based on Monte Carlo and two-temperature model method are used to calculate the damage threshold of Pt film with silicon (Si) substrate. The related photon energies are range from 5 to 30 keV, and the grazing incidence angles are 2 and 3 mrad, respectively. The results show that there are two energy absorption peaks, which are on the Pt film's surface and the interface between Pt and Si substrate. As the photon energy increases, the amount of the energy absorption shows opposite behavior in these two positions. It is mainly attributed to the increased photoelectron collision length. The damage threshold can reach the largest value at 1275 J/cm² with the condition of 10 keV and 2 mrad. Besides, the variation of reflectivity is positively correlated with damage threshold. Based on the results, for above 10 keV, it is recommended that 2 mrad is the suitable incident grazing angle. It will be instructive for engineering application and experimental design.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"725 ","pages":"Article 418227"},"PeriodicalIF":2.8,"publicationDate":"2025-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145885396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Structural and photoelectrical properties of an MDMO-PPV/n-Si hybrid heterojunction photodiode for broadband detection","authors":"Abdullah Karaca ,&nbsp;Dilber Esra Yıldız ,&nbsp;Ali Akbar Hussaini ,&nbsp;Murat Yıldırım ,&nbsp;Bayram Gündüz","doi":"10.1016/j.physb.2025.418225","DOIUrl":"10.1016/j.physb.2025.418225","url":null,"abstract":"<div><div>Organic–inorganic hybrid photodiodes are attractive for low-cost, broadband photodetection, yet the role of the polymer/Si interface on power- and wavelength-dependent performance is still not fully clarified. In this study, we fabricate a simple Al/MDMO-PPV/n-Si/Al heterojunction photodiode using a solution-processed MDMO-PPV interlayer and systematically correlate its structural, optical and electrical characteristics. UV–Vis spectroscopy reveals a pronounced absorption band at <span><math><mrow><mn>478</mn><mi>n</mi><mi>m</mi></mrow></math></span>, and Tauc analysis yields a direct optical band gap of <span><math><mn>2.28</mn><mspace></mspace><mi>eV</mi></math></span>. XRD and SEM measurements indicate a predominantly amorphous, porous polymer film with short-range order, providing interconnected pathways for charge transport. Current–voltage measurements under light illumination from 20 to 100 <span><math><msup><mi>mWcm</mi><mrow><mo>-</mo><mn>2</mn></mrow></msup></math></span> show clear rectification with negligible dark current. Thermionic-emission and Cheung analyses give ideality factors of <span><math><mrow><mn>3.0</mn><mo>–</mo><mn>3.5</mn></mrow></math></span> and zero-bias barrier heights of <span><math><mn>0.69</mn><mo>–</mo><mn>0.74</mn><mspace></mspace><mi>eV</mi></math></span>, while the photocurrent follows a power law <span><math><mrow><msub><mi>I</mi><mrow><mi>p</mi><mi>h</mi></mrow></msub><mo>∝</mo><msup><mi>P</mi><mn>1.42</mn></msup></mrow></math></span>, evidencing trap-assisted photoconduction. The device operates over 300–1050 nm, where the responsivity (R) increases from <span><math><mrow><mn>0.15</mn></mrow></math></span> to about <span><math><mn>0</mn><mo>.</mo><mn>42</mn><mspace></mspace><mi>A</mi><msup><mi>W</mi><mrow><mo>-</mo><mn>1</mn></mrow></msup></math></span>, the photosensitivity (K) rises to <span><math><mrow><mo>≈</mo><mn>4</mn><mo>−</mo><mn>13</mn></mrow></math></span>, and the specific detectivity (D) improves from <span><math><mo>∼</mo><mn>1.1</mn><mo>×</mo><msup><mn>10</mn><mn>10</mn></msup><mspace></mspace><mi>t</mi><mi>o</mi><mspace></mspace><mo>∼</mo><mn>1.8</mn><mo>×</mo><msup><mn>10</mn><mn>10</mn></msup><mspace></mspace><mi>Jones</mi></math></span>. Time-resolved measurements at <span><math><mrow><mn>0</mn><mi>V</mi></mrow></math></span> bias yield rise and fall times of 0.70 s and 0.94 s, respectively. These results demonstrate that an MDMO-PPV interlayer can efficiently extend n-Si photodiodes into the visible–NIR region and provide bias-free broadband detection, offering a scalable and low-cost platform for next-generation optoelectronic and sensing applications.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"725 ","pages":"Article 418225"},"PeriodicalIF":2.8,"publicationDate":"2025-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145927525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"High-pressure transition from metallic to semiconductor in newly discovered stable NaRuH3: Electronic band structure, elastic constants and mechanical properties","authors":"Seher Akbar ,&nbsp;Xin Liu ,&nbsp;Muhammad Imtiaz Rashid ,&nbsp;Khurram Shahzad ,&nbsp;Aishah Binti Mahpudz ,&nbsp;Arshid Mahmood Ali ,&nbsp;Yazen M. Alawaideh ,&nbsp;Hala Ghannam","doi":"10.1016/j.physb.2025.418226","DOIUrl":"10.1016/j.physb.2025.418226","url":null,"abstract":"<div><div>This study addresses the subject of high pressure metallic to semiconducting transition behavior of NaRuH₃, including electronic band structure, elastic constants, mechanical properties and hydrogen storage capacity under different pressure conditions. Calculated through the density functional theory, we explore how NaRuH₃ is affected by pressure in regard of its structural, electronic and mechanical characteristics. The findings show an immense opening of the band gap under pressure moving it out of its metallic status at ambient pressure and into the semiconducting status at 220 GPa–500 GPa. The material is found mechanically stable at higher pressure even at 500 GPa. The mechanical strength of the material is improved with the lattice compression since bulk modulus, shear moduli, and Young's modulus are rising quite abruptly, which means that the structure is more rigid and stable. In addition, both Debye temperature and the sound velocity drastically rise under increasing pressure to indicate an increment in atomic interactions and enhanced thermal and mechanical properties. The positive result of the influence of pressure on the hydrogen storage capacity of the material is also shown by the analysis; thus, the NaRuH₃ material with high pressure was more positive as far as hydrogen absorption and stability are concerned. The study has also revealed the significant importance of pressure in the optimization of NaRuH₃ to apply in hydrogen storage and energy activities, thereby contending it as a suitable candidate of advanced hydrogen storage technologies.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"725 ","pages":"Article 418226"},"PeriodicalIF":2.8,"publicationDate":"2025-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145885387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}