Physica B-condensed Matter最新文献_第3页

Aharonov-Bohm effect in a biphenyl system: relations between torsion angle, magnetic flux and electrical current 联苯体系中的Aharonov-Bohm效应：扭转角、磁通量和电流的关系

IF 2.8 3区物理与天体物理

Physica B-condensed Matter Pub Date : 2025-06-09 DOI: 10.1016/j.physb.2025.417471

A.C.L. Moreira , J.V. Nascimento , Roberta P. Dias , Júlio C.S. da Silva

{"title":"Aharonov-Bohm effect in a biphenyl system: relations between torsion angle, magnetic flux and electrical current","authors":"A.C.L. Moreira , J.V. Nascimento , Roberta P. Dias , Júlio C.S. da Silva","doi":"10.1016/j.physb.2025.417471","DOIUrl":"10.1016/j.physb.2025.417471","url":null,"abstract":"<div><div>This work presents a theoretical investigation of charge transport through a two-terminal biphenyl device under an external magnetic field, focusing on the Aharonov–Bohm effect. The Landauer formalism is employed, with the electronic structure described at the tight-binding (TB) level and the self-energies treated within the wide band limit approximation. Additionally, a decimation technique is applied to enable an analytical treatment. The influence of magnetic flux through the molecular rings is examined in two distinct scenarios: (i) varying the magnitude of the magnetic field while keeping the torsion angle fixed, and (ii) varying the torsion angle while maintaining a constant magnetic field. In the first case, we observe an increased electrical current with increasing magnetic flux. In the second case, the current increases as the magnetic flux decreases. By analyzing the dependence of the electronic current on the torsion angle and the magnetic flux, we uncover key mechanisms underlying quantum interference in this system.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"714 ","pages":"Article 417471"},"PeriodicalIF":2.8,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144253545","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}

引用次数: 0

Optical conductance and polarization of the monolayer graphene in the presence of Rashba spin orbit interaction and electromagnetic wave 在Rashba自旋轨道相互作用和电磁波存在下单层石墨烯的光电导和极化

IF 2.8 3区物理与天体物理

Physica B-condensed Matter Pub Date : 2025-06-09 DOI: 10.1016/j.physb.2025.417495

A. Naifar , C.A. Duque , K. Hasanirokh

{"title":"Optical conductance and polarization of the monolayer graphene in the presence of Rashba spin orbit interaction and electromagnetic wave","authors":"A. Naifar , C.A. Duque , K. Hasanirokh","doi":"10.1016/j.physb.2025.417495","DOIUrl":"10.1016/j.physb.2025.417495","url":null,"abstract":"<div><div>We present a theoretical investigation of the optical conductivity of graphene layer in the presence of Rashba spin-orbit coupling (SOC). By employing the massless Dirac description, we evaluate the combined impacts of the Rashba strength and chemical potential on the inter and intra conductivity within the sample. Our numerical findings revealed that the conductivity and polarization are highly sensitive to these pivotal highlighted parameters. Real and imaginary parts of both spin-dependent optical conductivity <span><math><mrow><msup><mi>σ</mi><mrow><mi>i</mi><mi>n</mi><mi>t</mi><mi>r</mi><mi>a</mi></mrow></msup></mrow></math></span> and <span><math><mrow><msup><mi>σ</mi><mrow><mi>i</mi><mi>n</mi><mi>t</mi><mi>e</mi><mi>r</mi></mrow></msup></mrow></math></span> behave differently with respect to the relevant managing factors and could be fine-tuned to advance spintronics. The imaginary parts exhibited strong sensitivity to changes in both λ and μ. Moreover, the dynamic response of the inspected system, particularly in terms of energy absorption and dissipation, is heavily influenced by the modulation of (λ, μ) pair. More importantly, the computational outcomes evidenced that the optical characteristics of this system differ significantly from those of a graphene layer due to the Rashba coupling incorporation. Spin-dependent optical conductivity can unlock new functionalities and enhance the performance of graphene in both spin-based electronics and light-based technologies, offering promising pathways for next-generation devices.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"714 ","pages":"Article 417495"},"PeriodicalIF":2.8,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144263193","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}

引用次数: 0

Synthesis of reduced graphene oxide decorated with cuprite nanoparticles for energy-storage devices: Dielectric properties and electrical conductivity 用于储能器件的铜纳米粒子修饰的还原氧化石墨烯的合成：介电性能和导电性

IF 2.8 3区物理与天体物理

Physica B-condensed Matter Pub Date : 2025-06-08 DOI: 10.1016/j.physb.2025.417490

S.M. Al-Moayid , H. Algarni , H. Elhosiny Ali , Yasmin Khairy

{"title":"Synthesis of reduced graphene oxide decorated with cuprite nanoparticles for energy-storage devices: Dielectric properties and electrical conductivity","authors":"S.M. Al-Moayid , H. Algarni , H. Elhosiny Ali , Yasmin Khairy","doi":"10.1016/j.physb.2025.417490","DOIUrl":"10.1016/j.physb.2025.417490","url":null,"abstract":"<div><div>This work reports a single‐step hydrothermal synthesis of reduced graphene oxide (rGO) uniformly decorated with cuprite (Cu<sub>2</sub>O) nanoparticles. Unlike conventional multi-step methods, this approach enables in-situ reduction and nanoparticle anchoring in a single step, ensuring strong interfacial contact and uniform Cu<sub>2</sub>O NP dispersion (7–43 nm) across the rGO sheets. By adjusting the Cu<sub>2</sub>O loading up to 0.05 g, the indirect bandgap narrows from 1.97 eV (pure rGO) to 0.12 eV, and the direct bandgap from 4.0 eV to 2.6 eV. At 1 kHz, the real permittivity (<em>ε</em>′) rises from ∼145 (rGO) to >230 (rGO/0.05 g Cu<sub>2</sub>O), indicating ≈60 % increase in energy‐storage capability. AC conductivity increases by nearly two orders of magnitude compared to bare rGO, reflecting enhanced carrier mobility and defect‐state hopping induced by Cu<sub>2</sub>O. XRD, Raman, XPS, and TEM all confirm effective GO reduction and crystalline Cu<sub>2</sub>O formation with strong interfacial contact. These tunable improvements demonstrate that Cu<sub>2</sub>O/rGO nanocomposites are promising for flexible electronics, high‐performance supercapacitors, and optoelectronic applications.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"714 ","pages":"Article 417490"},"PeriodicalIF":2.8,"publicationDate":"2025-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144240963","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}

引用次数: 0

Modeling of plasma nitriding and thermal annealing processes of austenitic stainless steel 奥氏体不锈钢的等离子体渗氮和热退火过程模拟

IF 2.8 3区物理与天体物理

Physica B-condensed Matter Pub Date : 2025-06-06 DOI: 10.1016/j.physb.2025.417487

Arvaidas Galdikas , Paulius Andriūnas , Thierry Czerwiec , Gregory Marcos , Teresa Moskaliovienė

{"title":"Modeling of plasma nitriding and thermal annealing processes of austenitic stainless steel","authors":"Arvaidas Galdikas , Paulius Andriūnas , Thierry Czerwiec , Gregory Marcos , Teresa Moskaliovienė","doi":"10.1016/j.physb.2025.417487","DOIUrl":"10.1016/j.physb.2025.417487","url":null,"abstract":"<div><div>In plasma nitriding of austenite stainless steel experiments, nitrogen penetration depth profiles typically show a characteristic plateau. This is associated with the phase transition to expanded austenite and non-Fickian diffusion of nitrogen involving the trapping of nitrogen by Cr sites, baro-diffusion and concentration dependent diffusion coefficient mechanisms. However, recent studies on thermally annealed post-nitrided austenitic samples have revealed the presence of two plateaus in the nitrogen depth profile curves. This phenomenon is new and has never been considered, and it is of particular interest as it suggests the presence of additional processes distinct from those responsible for the formation of the first plateau during nitriding. This work aims to analyze the appearance, mechanisms and processes responsible for the formation of the second plateau in the nitrogen depth profile during post-nitriding thermal annealing. The primary hypothesis is that the second plateau forms due to nitride formation, which is supported by XRD spectra showing chromium nitride after thermal annealing. The new mathematical model was developed for nitriding with non-Fickian diffusion mechanisms and post-nitrided annealing. The simulations performed with the developed model demonstrated that, under specific conditions, the second plateau emerges, thereby confirming the model's capability to reproduce nitrogen depth profiles exhibiting two plateaus. In the paper, these conditions are analysed in detail, and the influence of various parameters (diffusion coefficient, internal lattice stresses, processing time, etc.) is quantitatively investigated and it reveals that the appearance of the second plateau is very sensitive to these parameters not only during simulations but also in experiments.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"714 ","pages":"Article 417487"},"PeriodicalIF":2.8,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144271232","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}

引用次数: 0

Tertiary heterojunction TiO2-Fe3O4/rGO composites for visible light-enhanced degradation of organic dyes in wastewater TiO2-Fe3O4/氧化石墨烯三级异质结复合材料可见光强化降解废水中的有机染料

IF 2.8 3区物理与天体物理

Physica B-condensed Matter Pub Date : 2025-06-06 DOI: 10.1016/j.physb.2025.417465

Thi Thuy Pham, Thi Thanh Thuy Le

{"title":"Tertiary heterojunction TiO2-Fe3O4/rGO composites for visible light-enhanced degradation of organic dyes in wastewater","authors":"Thi Thuy Pham, Thi Thanh Thuy Le","doi":"10.1016/j.physb.2025.417465","DOIUrl":"10.1016/j.physb.2025.417465","url":null,"abstract":"<div><div>Water pollution caused by organic dyes remains a critical global challenge, requiring innovative and sustainable solutions. In this study, we introduce a novel tertiary heterojunction photocatalyst, TiO<sub>2</sub>-Fe<sub>3</sub>O<sub>4</sub>/rGO, synthesized via a hydrothermal method, specifically designed for efficient visible-light-driven degradation of methylene blue (MB). Unlike conventional photocatalysts, the TiO<sub>2</sub>-Fe<sub>3</sub>O<sub>4</sub>/rGO composite integrates TiO<sub>2</sub>, Fe<sub>3</sub>O<sub>4</sub>, and reduced graphene oxide (rGO) to form a synergistic heterojunction, which significantly enhances charge carrier separation and accelerates electron transfer. Advanced characterizations, including XRD, FTIR, SEM, TEM, EDX, and UV–Vis spectroscopy, confirm its optimized structural, morphological, and optical properties. The TiO<sub>2</sub>-Fe<sub>3</sub>O<sub>4</sub>/rGO photocatalyst demonstrates exceptional degradation efficiency, exceeding 95 % within 120 min, and retains over 85 % activity after four consecutive cycles, showcasing its outstanding stability. This remarkable performance is driven by the synergistic interaction between TiO<sub>2</sub>, Fe<sub>3</sub>O<sub>4</sub>, and rGO, which boosts reactive oxygen species (•O<sub>2</sub><sup>−</sup>, •OH) generation. As a cost-effective, robust, and scalable material, TiO<sub>2</sub>-Fe<sub>3</sub>O<sub>4</sub>/rGO offers a promising solution to the challenge of organic dye pollution in wastewater treatment. This study highlights the transformative potential of tailored heterojunction photocatalysts, paving the way for sustainable water treatment technologies driven by visible light.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"714 ","pages":"Article 417465"},"PeriodicalIF":2.8,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144263191","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}

引用次数: 0

Development of NaCaLa(MoO4)3:Sm3+ orange-red emitting phosphors with high color purity and thermal stability 高色纯度、高热稳定性的NaCaLa(MoO4)3:Sm3+橘红色发光荧光粉的研制

IF 2.8 3区物理与天体物理

Physica B-condensed Matter Pub Date : 2025-06-06 DOI: 10.1016/j.physb.2025.417489

K. Aravind, P. Samuel

{"title":"Development of NaCaLa(MoO4)3:Sm3+ orange-red emitting phosphors with high color purity and thermal stability","authors":"K. Aravind, P. Samuel","doi":"10.1016/j.physb.2025.417489","DOIUrl":"10.1016/j.physb.2025.417489","url":null,"abstract":"<div><div>A series of NaCaLa(MoO<sub>4</sub>)<sub>3</sub>:Sm<sup>3+</sup> orange-red phosphors were synthesized via conventional solid-state reaction technique and their phase purity, luminescence characteristics, and thermal stability were investigated in detail. Under excitation at 405 nm, NaCaLa(MoO<sub>4</sub>)<sub>3</sub>:Sm<sup>3+</sup> phosphors exhibit several emissions around the orange-red region, with an intense peak at 645 nm arising from the electric dipole transition of Sm<sup>3+</sup>, which is significantly enhanced by the asymmetric local environment. The optimum Sm<sup>3+</sup> concentration for NaCaLa<sub>1-x</sub>(MoO<sub>4</sub>)<sub>3</sub>:xSm<sup>3+</sup> phosphor was determined to be 6 %. The optimized NaCaLa<sub>0.94</sub>(MoO<sub>4</sub>)<sub>3</sub>:0.06Sm<sup>3+</sup> phosphor shows a color purity of 98.7 % and an internal quantum efficiency (IQE) of 38.04 %. Furthermore, at a temperature of 150 °C, the NaCaLa<sub>0.94</sub>(MoO<sub>4</sub>)<sub>3</sub>:0.06Sm<sup>3+</sup> retained 91.47 % of its room-temperature emission intensity, demonstrating remarkable thermal stability. Based on the results, the strong 645 nm emission under nUV excitation highlights their potential for red phosphors in phosphor-converted WLEDs.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"714 ","pages":"Article 417489"},"PeriodicalIF":2.8,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144240962","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}

引用次数: 0

Strain induced high thermoelectric performance of ScAgX (X=Si, Ge, Sn) half- Heusler alloys: A first principles approach 应变致高热电性能ScAgX （X=Si, Ge, Sn）半Heusler合金：第一性原理方法

IF 2.8 3区物理与天体物理

Physica B-condensed Matter Pub Date : 2025-06-06 DOI: 10.1016/j.physb.2025.417488

Rekha Rani, M.M. Sinha

{"title":"Strain induced high thermoelectric performance of ScAgX (X=Si, Ge, Sn) half- Heusler alloys: A first principles approach","authors":"Rekha Rani, M.M. Sinha","doi":"10.1016/j.physb.2025.417488","DOIUrl":"10.1016/j.physb.2025.417488","url":null,"abstract":"<div><div>Here we have studied the effect of strain (Tensile & Compressive) on the stability, electronic, mechanical and thermoelectric properties of ScAgX (X = Si, Ge, Sn) Half- Heusler (HH) materials. Firstly, stability analysis of these compounds has done by computing frequency curve and calculating energies. Phonon dispersion curve indicates that these compounds are stable up to −24 % compressive strain. Whereas on the application of tensile strain, ScAgGe is found stable to a high degree of strain. It is stretchable up to 12 % tensile strain, on the other hand ScAgSi and ScAgSn are stretchable up to 8 %. Calculated value of formation energy and cohesive energy, delivers idea about the strength of bonding between the atoms. These energies approach positive values on imposing the higher degree of strain which indicates the less stability of compounds on higher value of strain. After the confirmation of bearable value of strain from the stability criteria, we have explored the electronic properties under the respective value of strain. Electronic band structure shows that band gap gets reduced under the compressive strain and after a certain value these compounds shows the metallic nature. Whereas the band gap gets broadened under the tensile strain. For the application purpose, thermoelectric performance has been evaluated under the strained conditions. Lattice thermal conductivity gets reduced under the tensile strain whereas it increases under the compressive strain. ScAgSn shows the minimum lattice thermal conductivity among these compounds at 4 % strain. Figure of merit (ZT) for these compounds gets enhanced under the strained conditions. For ScAgSi ZT value increases from 0.12 to 0.18, ScAgGe shows enhancement in ZT value from 0.08 to 0.14 and ScAgSn has increased ZT value from 0.16 to 0.40.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"714 ","pages":"Article 417488"},"PeriodicalIF":2.8,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144229897","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}

引用次数: 0

Spin ballistic transport and conductance characteristics in p-type narrow-channel semiconductor devices p型窄通道半导体器件的自旋弹道输运和电导特性

IF 2.8 3区物理与天体物理

Physica B-condensed Matter Pub Date : 2025-06-05 DOI: 10.1016/j.physb.2025.417411

Chiang-Kuei Tsai , Chi-Shung Tang , Nzar Rauf Abdullah , Vidar Gudmundsson

引用次数: 0

Exploring the structural, magnetic, magnetocaloric and magnetoresistance behaviour of La2/3Sr1/3Mn(1-x)CrxO3 with varying Cr content 探索不同Cr含量的La2/3Sr1/3Mn(1-x)CrxO3的结构、磁性、磁热学和磁电阻行为

IF 2.8 3区物理与天体物理

Physica B-condensed Matter Pub Date : 2025-06-05 DOI: 10.1016/j.physb.2025.417486

C.P. Reshmi, A.R. Ramesh

{"title":"Exploring the structural, magnetic, magnetocaloric and magnetoresistance behaviour of La2/3Sr1/3Mn(1-x)CrxO3 with varying Cr content","authors":"C.P. Reshmi, A.R. Ramesh","doi":"10.1016/j.physb.2025.417486","DOIUrl":"10.1016/j.physb.2025.417486","url":null,"abstract":"<div><div>Chromium-substituted La<sub>2/3</sub>Sr<sub>1/3</sub>MnO<sub>3</sub> ceramics were prepared using the conventional solid state synthesis route. Rietveld refinement was performed for structural analysis, revealing rhombohedral symmetry and a uniform perovskite phase. The analysis indicates a systematic decrease in unit cell volume and lattice parameter with increasing Cr content. Temperature dependent magnetization data show a well-defined transition exhibiting spin/cluster glass behavior. La<sub>2/3</sub>Sr<sub>1/3</sub>Mn<sub>0.9</sub>Cr<sub>0.1</sub>O<sub>3</sub> shows a magnetocaloric effect of 2.11 J kg<sup>−1</sup> K<sup>−1</sup> at 316 K under a 5 T magnetic field. A comprehensive analysis of field-dependent magnetization, Arrott plots, and magnetic entropy change (−ΔS<sub>M</sub>) for x = 0.1 and x = 0.33 compositions highlights their second-order magnetic phase transitions. Resistivity analysis reveals that Cr substitution effectively enhances magnetoresistance at room temperature, with values of ∼12.5 % for x = 0.03 and ∼19 % for x = 0.1. These results underscore the potential of these compositions for applications requiring tunable magnetoresistance across a broad temperature range.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"714 ","pages":"Article 417486"},"PeriodicalIF":2.8,"publicationDate":"2025-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144240961","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}

引用次数: 0

Investigation of optical properties of gapped monolayer graphene under magnetic field with nearest and next-nearest-neighbor effects 最近邻和次近邻效应下单层石墨烯的光学性质研究

IF 2.8 3区物理与天体物理

Physica B-condensed Matter Pub Date : 2025-06-05 DOI: 10.1016/j.physb.2025.417410

Farshad Azizi , Hamed Rezania

引用次数: 0