Physica B-condensed Matter最新文献

{"title":"Correlation between structure and physical properties in Cu/Al-substituted barium hexaferrites ((Ba1–xCux)(AlxFe12–x)O19; x = 0.0 to 1.0)","authors":"G. Pushpalatha ,&nbsp;A. GuruSampath Kumar ,&nbsp;T. RavindraReddy ,&nbsp;K. Suresh Babu","doi":"10.1016/j.physb.2025.417874","DOIUrl":"10.1016/j.physb.2025.417874","url":null,"abstract":"<div><div>This study investigated the structural, magnetic, optical and vibrational properties of (Ba_1–xCu_x)(Al_xFe_12–x)O₁₉ hexaferrite nanoparticles synthesized by a simple wet-chemical c-precipitation method at the substitution level of x = 0.0–1.0. X-ray diffraction confirmed a single-phase hexagonal structure with lattice compression attributed to the smaller ionic radii of Cu²⁺ and Al³⁺. The crystallite size remained consistent at approximately 120 nm across the samples. Magnetic analysis revealed superparamagnetic behaviour at higher substitution levels, with decreased magnetization and coercivity resulting from site-specific occupation by Al³⁺ and Cu²⁺ ions. Nonlinear optical measurements using the Z-scan technique at 532 nm have shown a strong optical limiting behavior with two-photon absorption coefficients ranging from 6.3 × 10⁻¹¹ to 9 × 10⁻¹¹ m/W, underscoring their potential for photonic applications. FTIR spectroscopy confirmed metal–oxygen bond vibrations and the band shifts consistent with cationic substitution. These results highlight the tunable multifunctionality of Cu/Al-substituted Ba-hexaferrites, making them promising candidates for magnetic and optoelectronic devices.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"717 ","pages":"Article 417874"},"PeriodicalIF":2.8,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145221149","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 of silicene-based photosensor for carbon-based gas molecules","authors":"Fateme Alaee,&nbsp;Fatemeh Ostovari’,&nbsp;Mohammad Ali Sadeghzadeh","doi":"10.1016/j.physb.2025.417870","DOIUrl":"10.1016/j.physb.2025.417870","url":null,"abstract":"<div><div>This study simulates a silicene-based photosensor designed for the detection of carbon-based gaseous molecules, such as carbon monoxide (CO), carbon dioxide (CO₂), and methane (CH₄). Using an armchair-edge silicene nanoribbon as the active region of this sensor, we investigated the sensitivity, and selectivity in dark and light conditions at different wavelengths. In the dark condition, the smallest current change of sensors was related to the presence of CH₄. Under illuminated conditions, the sensor sensitivity to CO, CO₂, and CH₄ increased to 2.9, 9.7, and 2.28, respectively, compared to dark conditions. A similar pattern was observed in selectivity, with more pronounced changes in the selectivity of carbon dioxide over methane under illuminated conditions compared to dark conditions. This research confirmed that illumination significantly enhances both the sensitivity and selectivity. Furthermore, it was noted that the recovery time for CH₄ and CO₂ sensing is significantly shorter than that for CO gas.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"718 ","pages":"Article 417870"},"PeriodicalIF":2.8,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145271227","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":"Mn-doped barium zirconate nanoparticles for high-performance photocatalyst applications","authors":"C. Chinnusamy,&nbsp;R. Thiyagarajan","doi":"10.1016/j.physb.2025.417868","DOIUrl":"10.1016/j.physb.2025.417868","url":null,"abstract":"<div><div>The high photocatalytic efficacy was demonstrated by the straightforward co-precipitation approach used in this work to synthesis pure and Mn-doped barium zirconate (Ba_xMn_1-xZrO₃). The photocatalytic activity was examined to remove the Methylene Blue (MB) dye. Powder X-ray diffraction technique (XRD) is used to analyze the formation of single-phase cubic perovskites and FESEM was used to estimate the nanoparticles' shape. FTIR spectra showed that ABO₃ perovskites have a noticeable band between 400 and 3500 cm⁻¹. Various characterizations like Raman spectroscopy, Photoluminescence (PL) spectroscopy, UV–VIS spectroscopy and Photocatalytic activity was also used to analyze the synthesized samples. The estimated band gap values, ranging from 3.65 to 3.85 eV, suggest that nanocrystalline Ba_xZr_1-xO₃ is a viable UV–visible light-activated photocatalyst at excitation wavelengths less than 800 nm. Methylene blue (MB) breaks down at a concentration of Mn³⁺ (0.1M) when exposed to visible light, Mn³⁺ (0.1M) nanoparticles destroyed the dye by about 96 %; the efficacy of the photocatalyst is strongly reliant on raising the Mn³⁺ concentration and creating defects.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"718 ","pages":"Article 417868"},"PeriodicalIF":2.8,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145270854","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":"Nonlinear optical response of zigzag carbon nanotubes under mechanical strain","authors":"Raad Chegel","doi":"10.1016/j.physb.2025.417867","DOIUrl":"10.1016/j.physb.2025.417867","url":null,"abstract":"<div><div>This study investigates the strain-induced modifications in the linear and nonlinear optical properties of zigzag carbon nanotubes (CNTs). The analyzed optical functions include the linear absorption spectra, the electro-optic effect (QEO) and the two-photon absorption spectrum. A tight-binding model, combined with the density matrix formalism and perturbation theory, is employed to analyze these properties, considering all interband transitions across the entire Brillouin zone. The results demonstrate that both tensile and compressive strains significantly alter the optical responses of zigzag CNTs. In linear optical spectra, strain modifies the positions and intensities of absorption peaks, particularly those associated with E₁₁ and E₂₂ transitions. Similarly, strain also impacts the nonlinear optical responses, leading to noticeable peak shifts and intensity variations, particularly in the energy region below the band gap. The observed red- and blue-shifts of peaks vary depending on the specific category of zigzag CNTs, highlighting distinct strain-dependent behaviors. Furthermore, all strain-dependent optical characteristics demonstrate that semiconducting zigzag CNTs exhibit two distinct response patterns, related to their classification differences. The strain-induced shifts in nonlinear optical peaks suggest potential applications in strain-engineered photonic devices, such as ultrafast optical modulators and nonlinear optical switches.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"717 ","pages":"Article 417867"},"PeriodicalIF":2.8,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145268025","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":"Anisotropic pressure dependence of the in-plane effective mass in optimally doped Hg-based cuprates: a Casimir energy approach","authors":"Abdullo Ahadov ,&nbsp;Davron Dzhuraev","doi":"10.1016/j.physb.2025.417864","DOIUrl":"10.1016/j.physb.2025.417864","url":null,"abstract":"<div><div>The effect of external pressure on Hg-based cuprate superconductors is central to understanding their anisotropic electronic behavior. While the pressure dependence of <span><math><mrow><msub><mi>T</mi><mi>c</mi></msub></mrow></math></span> is well studied, its influence on the effective mass of charge carriers is poorly known, especially under uniaxial compression. Here, we analyze uniaxial and hydrostatic pressure derivatives of the in-plane effective mass <span><math><mrow><msup><msub><mi>m</mi><mrow><mi>a</mi><mi>b</mi></mrow></msub><mo>∗</mo></msup></mrow></math></span> in optimally doped Hg-12(n−1)n high-<span><math><mrow><msub><mi>T</mi><mi>c</mi></msub></mrow></math></span> cuprates within the Casimir energy framework. Analytical expressions are derived and applied to the first five Hg-12(n−1)n members. Calculations show that <em>a</em>-axis and hydrostatic pressure reduce <span><math><mrow><msup><msub><mi>m</mi><mrow><mi>a</mi><mi>b</mi></mrow></msub><mo>∗</mo></msup></mrow></math></span>, whereas <em>c</em>-axis pressure increases it. The effect's magnitude and anisotropy decrease with increasing <span><math><mrow><msub><mtext>CuO</mtext><mn>2</mn></msub></mrow></math></span> layers, with Hg-1245 exhibiting an anomalous response linked to lattice instabilities and interlayer decoupling. Results agree with Uemura's universal relation and other theories, offering quantitative predictions to guide future uniaxial-pressure experiments.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"718 ","pages":"Article 417864"},"PeriodicalIF":2.8,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145223250","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 investigation of triaxial strain effects on the physical properties of Rb2TiBr6 double perovskite for photocatalytic and thermoelectric applications","authors":"A. Jabar ,&nbsp;Y. Selmani ,&nbsp;S. Benyoussef ,&nbsp;L. Bahmad","doi":"10.1016/j.physb.2025.417855","DOIUrl":"10.1016/j.physb.2025.417855","url":null,"abstract":"<div><div>In this study, we conduct a comprehensive computational investigation of the compound Rb₂TiBr₆, focusing on the influence of triaxial strain on its mechanical, electronic, optical, photocatalytic and thermoelectric properties. All calculations were performed within the framework of density functional theory (DFT) using the Wien2k computational package. Structural optimization was carried out with the Perdew–Burke–Ernzerhof generalized gradient approximation (PBE-GGA), while the modified Becke–Johnson (mBJ) potential was employed to evaluate the electronic and optical properties. In addition, the thermoelectric performance was assessed by combining DFT results with semi-classical Boltzmann transport theory (SBT). The optimized structure of Rb₂TiBr₆ adopts a cubic phase with a lattice parameter of 10.594 Å. The calculated elastic constants confirm its mechanical stability under different strain conditions. Further analysis indicates that the compound exhibits ductile and anisotropic characteristics, with bonding predominantly of ionic nature. The electronic band structure and density of states (DOS) confirm that Rb₂TiBr₆ is a semiconductor with an indirect band gap (Γ–X), which increases from 1.952 eV to 2.115 eV as the applied strain varies from 0 % to 6 %. Optical analysis reveals strong absorption above 10⁴ cm⁻¹ and low reflectivity in the visible region, highlighting its potential for photovoltaic applications. Furthermore, the material exhibits excellent photocatalytic activity, underscoring its suitability for water-splitting processes. Thermoelectric analysis reveals that the application of strain enhances the figure of merit (ZT), reaching ∼3.5 at low temperature, which underscores the strong potential of Rb₂TiBr₆ for efficient thermoelectric energy conversion.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"717 ","pages":"Article 417855"},"PeriodicalIF":2.8,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145221049","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":"Advanced electrochemical insights and biomedical activities of WO3/TiO2 heterostructures","authors":"Satam Alotibi ,&nbsp;Awais Khalid ,&nbsp;Wajeehah Shahid ,&nbsp;Maria Khizar","doi":"10.1016/j.physb.2025.417838","DOIUrl":"10.1016/j.physb.2025.417838","url":null,"abstract":"<div><div>This study synthesized WO₃/TiO₂ nanocomposites using a controlled ex-situ technique. The DPPH method was used to prepare the WO3/TiO2 for antioxidant activity. Our findings showed that the highest Percentage of antioxidant activity of WO₃/TiO₂ exhibited DPPH inhibition activity values of 61.21 %, 64.56 %, and 64.75 %, respectively, due to the activity of DPPH in scavenging radicals. The observed inhibition zones for <em>E. coli</em> and Klebsiella were 25.64 mm and 24.17 mm. For electrochemical studies, at different current densities (0.8, 1.0, 1.2, and 1.4 A g⁻¹), the TiO₂-WO₃ exhibits the longest discharge time. For specific capacitance, TiO₂-WO₃ composite shows the maximum capacitance, reaching 80 F g⁻¹ at 0.8 A g⁻¹ and holding onto 59.5 F g⁻¹ at 1.4 A g⁻¹. In terms of energy density, TiO₂-WO₃ composite reached a maximum of 6.4 Wh kg⁻¹ at 0.8 A g⁻¹. This study indicates that WO₃/TiO₂ nanocomposites hold significant potential for future biomedical and high-performance supercapacitors.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"717 ","pages":"Article 417838"},"PeriodicalIF":2.8,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145221147","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-dependent polarization evolution of photoluminescence in Ruddlesden–Popper perovskite (PEA)2SnI4","authors":"Wei Tang ,&nbsp;Yanxin Han ,&nbsp;Enzheng Shi ,&nbsp;Linjun Li","doi":"10.1016/j.physb.2025.417839","DOIUrl":"10.1016/j.physb.2025.417839","url":null,"abstract":"<div><div>Ruddlesden–Popper (RP) tin halide perovskites attract lots of research interests for opto-electronic devices because of its smaller optical bandgaps, smaller effective masses for carriers and are less toxic compared to its lead-based counterparts. Lots of optical characterization have been done but discussion of polarization is relatively few. We use linear and circular polarization resolved spectroscopy to investigate the polarization property of (PEA)<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>SnI<span><math><msub><mrow></mrow><mrow><mn>4</mn></mrow></msub></math></span> from 4 K to room temperature and under external magnetic field, since polarization is a new degree of freedom for opto-electronic devices. We found that the absorption and photoluminescence of excitons in (PEA)<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>SnI<span><math><msub><mrow></mrow><mrow><mn>4</mn></mrow></msub></math></span> is linear polarized, and the degree of linear polarization decreases from 0.6 at 4 K to 0.08 at 290 K, and degree of circular polarization is zero. The polarization direction can be rotated by magnetic field at 2.4 deg per tesla. We also observed exciton fine structure of the band edge bright exciton, the energy splitting of two orthogonal states is only 3 meV. Our findings on such polarized exciton property can be benefit for opto-electronic devices application.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"717 ","pages":"Article 417839"},"PeriodicalIF":2.8,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145221148","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 investigation of half-metallic ferromagnetism and optical properties of magnesium-based Mg(Fe/Mn)2O4 spinels for spintronic and clean energy","authors":"E.M. Jalal ,&nbsp;H. Kerrai ,&nbsp;H. Saadi ,&nbsp;M. Salama ,&nbsp;A. Hasnaoui ,&nbsp;M. El Bouziani","doi":"10.1016/j.physb.2025.417849","DOIUrl":"10.1016/j.physb.2025.417849","url":null,"abstract":"<div><div>We utilized first principles calculations so as to investigate structural stability, optical, electronic, as well as magnetic properties for Mg(Fe/Mn)<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>4</mn></mrow></msub></math></span> spinel alloys. We showed that both compounds are ferromagnetic, with optimal lattice parameters of 8.47 Å for MgFe<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>4</mn></mrow></msub></math></span> and 10.07 Å for MgMn<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>4</mn></mrow></msub></math></span>. The electronic properties revealed that both compounds exhibit semiconductor behavior, with direct band gaps of 0.18 eV for MgFe<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>4</mn></mrow></msub></math></span> and 2.8 eV for MgMn<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>4</mn></mrow></msub></math></span> in the spin-down state, while displaying metallic behavior in the spin-up state. Additionally, the optical analysis indicates high absorption coefficients in the UV region, coupled with high reflectivity at 0 eV, highlighting their favorable optoelectronic characteristics. Furthermore, the magnetic analysis demonstrates that both compounds exhibit ferromagnetic properties, with magnetic moments approximating 5 <span><math><msub><mrow><mi>μ</mi></mrow><mrow><mi>B</mi></mrow></msub></math></span> for MgFe<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>4</mn></mrow></msub></math></span> and 4 <span><math><msub><mrow><mi>μ</mi></mrow><mrow><mi>B</mi></mrow></msub></math></span> for MgMn<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>4</mn></mrow></msub></math></span>. Based on these results, these alloys show potential as candidates for spintronic devices.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"717 ","pages":"Article 417849"},"PeriodicalIF":2.8,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145221155","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":"Electronic band structure, stability and thermoelectric performances of two phases of Cu2S: ab initio PAW approach","authors":"V.P. Zhukov ,&nbsp;E.V. Chulkov","doi":"10.1016/j.physb.2025.417850","DOIUrl":"10.1016/j.physb.2025.417850","url":null,"abstract":"<div><div>The electronic band structure calculations for β- and γ-phases of copper sulfide Cu₂S were performed by using the LDA + U and hybrid exchange-correlation potential approximations. The mechanical stability of both phases have been confirmed via calculations of elasticity constants. Based on the phonon spectra calculations it has been shown that the β-phase is dynamically unstable. This favours the transitions of copper atoms from positions inside the Cu₂S layers into the interlayer spacing. Within the framework of the Boltzmann-Onsager theory, considering the dependence of the electron relaxation time on the electron energy and wave vector, the calculations were performed for the electric conductivity, Seebeck coefficient, power factor and figure-of-merit. The concentration dependence of the figure-of-merit at a high amount of p-type carriers is shaped as an extremum curve because of the balance between a temperature-caused increase in the electrical conductivity and a decrease in the Seebeck coefficient. The maximum of figure-of-merit can be reached at a carrier concentration of 10²¹ 1/cm³ approximately.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"717 ","pages":"Article 417850"},"PeriodicalIF":2.8,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145221048","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}