Physica B-condensed Matter最新文献

{"title":"Probing the physical properties of rare earth metal based double perovskites Sr2Ce(Ni,Sn)O6 through first-principles investigations","authors":"Iftikhar Ahmed ,&nbsp;Calvyn T. Howells ,&nbsp;Mubashir Nazar ,&nbsp;Gamil A.A.M. Al-Hazmi","doi":"10.1016/j.physb.2026.418306","DOIUrl":"10.1016/j.physb.2026.418306","url":null,"abstract":"<div><div>This research work probes the physical attributes of rare earth metal-based double perovskites Sr₂CeNiO₆ and Sr₂CeSnO₆ using first-principles calculations with the generalized gradient approximation and modified Becke-Johnson (GGA + mBJ) method. To check their structural stability, tolerance (τ) and octahedral (μ) factors, and formation energy (ΔH) were calculated with calculated τ values of 0.90 and 0.91, and ΔH of −3.96 eV and −4.37 eV for respective Sr₂CeNiO₆ and Sr₂CeSnO₆. Mechanical firmness was further confirmed by means of elastic tensor based Born stability criteria. The electronic structures obtained from the mBJ method reveals direct band gaps of 1.55 eV and 2.44 eV, with Ce-4f states appearing near the conduction bands edge and effectively influencing the band dispersion. Optical conductivity analysis shows enhanced conductivity in the UV light, representing possible contender for optoelectronic technologies, such as UV detection and photovoltaic devices. Thermoelectric properties of Sr₂CeNiO₆ and Sr₂CeSnO₆ show favorable Seebeck coefficients and reduced thermal conductivity, resulting the ZT of 0.82 at 700 K and 0.77 at 500 K. These findings showcase the possibility of these rare earth based oxides for efficient energy conversion, making them perfect contenders for future-generation thermoelectric systems.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"727 ","pages":"Article 418306"},"PeriodicalIF":2.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146081204","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":"Investigations on luminescent properties of thermally stable Eu3+ doped Sr4Ca2W2O12 phosphor for high color purity in white LEDs and non-contact optical thermometry applications","authors":"Kanika Kardam,&nbsp;A.S. Rao,&nbsp;R.K. Sinha","doi":"10.1016/j.physb.2026.418319","DOIUrl":"10.1016/j.physb.2026.418319","url":null,"abstract":"<div><div>A series of Eu³⁺ ions doped SCW phosphors have been prepared using a solid-state reaction method. The XRD pattern confirms that the as-prepared phosphors have a monoclinic structure having a space group (P₁ 21/c₁). The presence of composition elements and their morphological behaviour were investigated using SEM and EDAX analysis, respectively. The UV–Vis diffuse reflectance spectra (DRS) were used to assess the phosphor's optical bandgap. The transition ⁵D₀ to ⁷F₂, which emits a strong red colour in the visible spectrum, is responsible for the peak with the highest intensity at 614 nm in the photoluminescence (PL) emission spectra, which were recorded under 465 nm excitation wavelength. The Commission Internationale de l'Eclairage (CIE) chromaticity coordinates of Sr₄Ca₂W₂O₁₂: xEu³⁺ (x = 4.0 mol%) of the optimized sample was found to be (0.6170,0.3778), which falls in the red region, has a high color purity of 98.71 % and correlated color temperature (CCT) of 1690 K. The photoluminescence (PL) decay characteristics exhibited a bi-exponential nature, while temperature-dependent PL (TDPL) measurements demonstrated notable thermal stability, with the material preserving 56.20 % of its emission intensity at 150 °C. With a thermal activation energy of 0.3998 eV and quantum efficiency of 98.16 % demonstrate that SCW phosphor is significantly more thermally stable. An FIR temperature measurement model was created with a maximum value of 1.43 % K⁻¹ for S_r, showing the sample's good optical temperature-measuring properties. According to the previously described findings, the synthesized SCW: xEu³⁺ phosphor samples can be used in both White LEDs as well as non-contact optical thermometry applications.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"727 ","pages":"Article 418319"},"PeriodicalIF":2.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146171109","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":"Sintering-temperature effects on cation redistribution and magnetic response of the Y2.97Gd0.03Fe4.97La0.03O12 ceramic","authors":"M. Gonçalves ,&nbsp;J. Penha-Caland ,&nbsp;C. Vilca-Huayhua ,&nbsp;J.A.H. Coaquira ,&nbsp;J. Matilla-Arias ,&nbsp;F. Guerrero ,&nbsp;Samuel F. Rodrigues ,&nbsp;Bartolomeu C. Viana ,&nbsp;Ramón R. Peña-Garcia","doi":"10.1016/j.physb.2026.418364","DOIUrl":"10.1016/j.physb.2026.418364","url":null,"abstract":"<div><div>In this work, we report a comprehensive investigation of the influence of sintering temperature (900, 1000, and 1100 °C) on the structural, morphological, and magnetic properties of the Y_2.97Gd_0.03Fe_4.97La_0.03O₁₂ garnet-type ceramic synthesized by the sol–gel method. Structural refinement confirms the predominance of the garnet phase in all samples and reveals a thermally induced emergence of a YFeO₃ secondary phase, quantified as 3.7 % at 1000 °C and 9.9 % at 1100 °C. Increasing the sintering temperature enhances crystallinity, increases the average crystallite size from 45 to 68 nm (≈51 %), and reduces the microstrain by ≈ 33 %. Infrared vibrational analysis shows red shifts in Fe–O stretching modes, indicating bond elongation and local lattice relaxation. Electron microscopy reveals grain growth and reduced porosity at 1000 °C, followed by abnormal coarsening and localized porosity at 1100 °C. Mössbauer spectroscopy demonstrates a temperature-dependent redistribution of Fe³⁺ across octahedral and tetrahedral sublattices and confirms the persistence of Fe²⁺ associated with oxygen-vacancy stabilization. This redistribution governs the magnetic response: the saturation magnetization increases from 15.37 emu g⁻¹ (900 °C) to 18.46 emu g⁻¹ at 1000 °C (≈20 %), then decreases to 15.27 emu g⁻¹ at 1100 °C in parallel with the growth of the secondary phase. Remanent magnetization follows the same trend, whereas the remanent-to-saturation ratio remains nearly constant at ≈0.3, consistent with a multi-domain configuration. Coercivity decreases from 62 to 46 Oe (≈26 %), reflecting grain-size-assisted domain-wall motion. Collectively, these results show that sintering temperature provides a quantitative route to tune structural relaxation, cation redistribution, and magnetic behavior in this co-doped garnet system. The sample sintered at 1000 °C exhibits the most favorable combination of crystallinity, controlled porosity, and maximized magnetization, offering a mechanism-based framework for designing soft-magnetic and microwave-grade ceramics.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"727 ","pages":"Article 418364"},"PeriodicalIF":2.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146171068","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":"Elastic modulus, strength, and ductility of TH graphyne: A comprehensive study of layers, defects, and thermal effects","authors":"Ruihua Ding ,&nbsp;Ye Tao ,&nbsp;Feng Zeng ,&nbsp;Fujiang Chen","doi":"10.1016/j.physb.2026.418272","DOIUrl":"10.1016/j.physb.2026.418272","url":null,"abstract":"<div><div>Recent theoretical studies have predicted that TH graphyne, a two-dimensional carbon allotrope with a unique sp–sp² hybridized structure, exhibits exceptional mechanical properties, including high tensile strength and tunable elastic behavior. These earlier investigations primarily focused on small-scale models and idealized loading conditions, suggesting that TH graphyne could serve as a promising candidate for advanced nanomechanical applications. However, the size-dependent mechanical response and failure mechanisms under realistic structural imperfections remain largely unexplored. In this study, we perform large-scale molecular dynamics simulations using AIREBO force field to investigate the mechanical behavior of TH graphyne nanosheets with varying sizes and edge morphologies. Our results reveal a clear reduction in both stiffness and strength with increasing system size, which is attributed to stress concentration at free edges and the increased likelihood of defect-initiated fracture. These findings align with established size effects observed in graphene and highlight the importance of edge quality in determining the effective mechanical performance of TH graphyne.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"727 ","pages":"Article 418272"},"PeriodicalIF":2.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146039948","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":"Simulation study of structural, phase transition, and glass transition behavior in Ga1-xInx alloys (x = 0.2–0.8)","authors":"Dung Nguyen Trong ,&nbsp;Tuan Tran Quoc ,&nbsp;Ştefan Ţălu","doi":"10.1016/j.physb.2026.418271","DOIUrl":"10.1016/j.physb.2026.418271","url":null,"abstract":"<div><div>This study investigates the effects of compositional and thermal factors on the structural properties, phase transitions, and glass transition temperature of Ga_1-xIn_x alloys (x = 0.2, 0.4, 0.5, 0.6, 0.8) using simulation methods. At 300 K, the calculated bond lengths for Ga–Ga, Ga–In, and In–In pairs are approximately 3.25 Å, 3.15 Å, and 3.05 Å, respectively. As the temperature decreases from 300 K to 4 K and the indium concentration increases from 20 % to 80 %, the total number of atoms in the system rises from 5,324 to 27,436. Despite these changes, the average bond length remains relatively stable, fluctuating around 3.15 Å. However, the total bonding energy of the system decreases significantly, contributing to an overall increase in structural smoothness and stability of the alloy. Furthermore, the glass transition temperature (T_g) of the GaIn alloy was determined to be approximately 188 K. These findings offer valuable insights into the temperature- and composition-dependent behavior of GaIn alloys and provide a theoretical foundation for their optimization in advanced semiconductor device applications.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"727 ","pages":"Article 418271"},"PeriodicalIF":2.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146081195","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":"Simultaneous two-photon absorption and self-defocusing in colloidal Cu-doped CdSe nanotetrapods","authors":"I.D. Laktaev ,&nbsp;S.G. Dorofeev ,&nbsp;A.M. Smirnov","doi":"10.1016/j.physb.2026.418324","DOIUrl":"10.1016/j.physb.2026.418324","url":null,"abstract":"<div><div>We report the first experimental investigation of nonlinear optical absorption in colloidal solutions of copper-doped CdSe nanotetrapods under two-photon excitation using femtosecond laser pulses. The nonlinear transmittance measurements reveal the simultaneous action of two-photon absorption and self-defocusing, resulting in pronounced asymmetry in open-aperture Z-scan profiles. The two-photon absorption coefficient was determined to be β = 0.14–0.20 cm/GW and the nonlinear refractive index ranged from – 4.9 × 10⁻¹⁶ to – 5.3 × 10⁻¹⁵ cm²/W, depending on the excitation intensity and nanostructure concentration. Additionally, we observed spatial self-phase modulation, manifested by the appearance of well-defined diffraction rings and a sharp decrease in transmittance at high laser pulse intensities. These findings demonstrate strong nonlinear optical responses in Cu-doped CdSe nanotetrapods and highlight their potential for high-sensitivity biosensing and advanced photonic applications.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"727 ","pages":"Article 418324"},"PeriodicalIF":2.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146081278","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":"Majorana signature in a diatomic Kitaev chain with dual non-Hermitian mechanisms","authors":"Cong Wang ,&nbsp;Li-Hui Jin ,&nbsp;Xiao-Qi Wang","doi":"10.1016/j.physb.2026.418379","DOIUrl":"10.1016/j.physb.2026.418379","url":null,"abstract":"<div><div>The band structure of a one-dimensional nonreciprocal diatomic Kitaev chain is investigated by introducing anti-<span><math><mrow><mi>P</mi><mi>T</mi></mrow></math></span>-symmetric imaginary potentials with the configuration <span><math><mrow><mo>(</mo><mi>i</mi><mi>γ</mi><mo>,</mo><mo>−</mo><mi>i</mi><mi>γ</mi><mo>,</mo><mo>−</mo><mi>i</mi><mi>γ</mi><mo>,</mo><mi>i</mi><mi>γ</mi><mo>)</mo></mrow></math></span>, where <span><math><mi>γ</mi></math></span> denotes the strength of the imaginary potential. It is found that non-Hermitian parameters and the modification of the unit cell induce multiple topological phase transitions in the system. When the chemical potential is set at zero energy, this system exhibits two purely real Majorana zero modes (MZMs) and four purely imaginary Su–Schrieffer–Heeger (SSH) edge modes, accompanied by a “Majorana-mixed-SSH” topological phase transition. In contrast, as the chemical potential deviates from zero, both Majorana modes and SSH edge modes emerge at finite imaginary potential strengths, and a phase transition from the SSH phase to the Majorana phase is observed. We argue that the modulating effect of non-Hermitian parameters on edge modes demonstrated in this work can provide theoretical support for understanding phase transitions and the generation of Majorana modes in non-Hermitian topological superconducting systems.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"727 ","pages":"Article 418379"},"PeriodicalIF":2.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146170951","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-frequency giant magnetoimpedance and giant stress-impedance behaviors in Metglas/magnetic nanofilms laminated composites for sensing application","authors":"Zhen Yang ,&nbsp;Yuanwei Shen ,&nbsp;Song Luo ,&nbsp;Wenguo Chen ,&nbsp;Mingjin Zhong ,&nbsp;Xuecheng Sun ,&nbsp;Chong Lei","doi":"10.1016/j.physb.2026.418374","DOIUrl":"10.1016/j.physb.2026.418374","url":null,"abstract":"<div><div>High-frequency giant magnetoimpedance (GMI) and giant stress-impedance (GSI) effects are promising for highly sensitive magnetic and stress sensing. In this work, laminated composites (LCs) based on Metglas 2714A ribbons coated with magnetic nanofilms were fabricated using photolithography, wet etching and magnetron sputtering. Three magnetic nanofilms, CoTaZr (S1), FeCoGa (S2) and CoFe₂O₄ (S3), were deposited at a thickness of 100 nm, and CoTaZr layers from 20 to 200 nm were further examined. The influence of nanofilm type and thickness on structure, morphology, magnetic properties and GMI or GSI performance was systematically analyzed. S1 showed the smoothest surface with roughness of about 11.46 nm and low coercivity of 4.8 Oe, and reached the highest GMI ratio of about 160 percent at 150 nm. S2 yielded the largest GSI of about 31 percent at 10 MPa. These results confirm that rational nanofilm design effectively enhances GMI or GSI responses.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"727 ","pages":"Article 418374"},"PeriodicalIF":2.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146170953","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":"First-principles analysis of the structural, electronic, optical, and mechanical features of XAgF4 (X = Li, Na, K)","authors":"Hussein Sabbah ,&nbsp;R. El Fdil ,&nbsp;A. Jabar ,&nbsp;Z. Fadil ,&nbsp;S. Idrissi ,&nbsp;L. Bahmad ,&nbsp;Chaitany Jayprakash Raorane ,&nbsp;Seong-Cheol Kim ,&nbsp;S. Saadaoui","doi":"10.1016/j.physb.2026.418329","DOIUrl":"10.1016/j.physb.2026.418329","url":null,"abstract":"<div><div>Density functional theory (DFT) within the local spin-density approximation with modified Becke-Johnson potential (LSDA-mBJ) is used to investigate the structural, mechanical, electronic, optical, and thermodynamic properties of the XAgF₄ (X = Li, Na, K) series. All compounds crystallize in a stable tetragonal <em>I</em>4/<em>mcm</em> structure. Elastic constants confirm their mechanical stability, with NaAgF₄ exhibiting the highest stiffness and KAgF₄ the greatest ductility. Electronic calculations reveal these materials are indirect semiconductors with band gaps ranging from 2.14 to 2.20 eV. Optical spectra indicate strong ultraviolet absorption and high refractive indices, while thermodynamic analysis confirms their thermal stability across the series. Systematic comparison illustrates how the cationic substitution from Li to K modifies lattice stability, mechanical response, electronic structure, and optical activity. This work elucidates the composition-property relationships in XAgF₄ fluorides and provides a theoretical foundation for designing halide-based materials for optoelectronic applications and protective coatings.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"727 ","pages":"Article 418329"},"PeriodicalIF":2.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146171003","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":"Synthesis and photocatalytic activity of the TiO2/g-C3N4 composites: Influence of the TiO2 particles morphology (rod or spherical) on degradation of organic dye","authors":"Olga V. Alekseeva,&nbsp;Valeriya D. Shibaeva,&nbsp;Andrew V. Noskov,&nbsp;Alexander V. Agafonov","doi":"10.1016/j.physb.2026.418302","DOIUrl":"10.1016/j.physb.2026.418302","url":null,"abstract":"<div><div>In this work, an original approach was proposed for obtaining spherical and rod-shaped titanium dioxide particles and the influence of TiO₂ particle morphology on the photocatalytic activity of TiO₂/g-C₃N₄ composites was investigated. Composites were synthesized using sol-gel methods to achieve the desired TiO₂ morphologies anchored onto g-C₃N₄. The synthesized materials were characterized using SEM-EDS, XRD, nitrogen vapor adsorption-desorption, and photoluminescence spectroscopy. It was found that, the specific surface area for TiO₂-sph/g-C₃N₄ (157 m²/g) was larger than that of TiO₂-rod/g-C₃N₄ (117 m²/g), which is an important factor for the photocatalytic activity. For the first time, a study was conducted on the influence of the photocatalyst particles morphology on the photocatalytic destruction of a mixture of organic dyes with different states in solution (Rhodamine B, Methylene Blue, Reactive Red 6C). It was found that the concentration of MB and RhB dyes decreased to zero for 60 min in the presence of the TiO₂-rod/g-C₃N₄ photocatalyst under UV irradiation. Results indicate that the specific morphology of TiO₂ significantly impacts the photocatalytic efficiency of the TiO₂/g-C₃N₄ composites, attributed to differences in surface area, charge carrier separation efficiency, and light absorption properties. This comparative study provides insights into structure-activity relationships for designing efficient heterojunction photocatalysts for wastewater remediation.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"727 ","pages":"Article 418302"},"PeriodicalIF":2.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146171111","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}