Physica B-condensed Matter最新文献

{"title":"Electrical conductivity and nonlinear dielectric properties of graphite-like carbon films at low frequencies","authors":"Grigorii V. Nenashev ,&nbsp;Igor A. Vrublevsky ,&nbsp;Andrey A. Ryabko ,&nbsp;Andrey N. Aleshin ,&nbsp;Vyacheslav A. Moshnikov","doi":"10.1016/j.physb.2026.418322","DOIUrl":"10.1016/j.physb.2026.418322","url":null,"abstract":"<div><div>This study investigates the structural, electrical properties, and impedance characteristics of thin graphite-like carbon films deposited by electron-beam evaporation and annealed in vacuum. Raman spectroscopy reveals that the films consist mainly of sp²-hybridized carbon with graphite-like clusters of approximately 9.5 nm. Current–voltage measurements indicate space-charge-limited conduction and trap states. Impedance spectroscopy shows two overlapping relaxation processes, modeled with an equivalent circuit of two parallel branches with resistive and constant phase elements. The calculated effective capacitances were <span><math><mrow><msub><mi>C</mi><mrow><mi>e</mi><mi>f</mi><mi>f</mi><mn>1</mn></mrow></msub><mo>=</mo><mn>4.09</mn><mo>∗</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>9</mn></mrow></msup><mspace></mspace><mi>F</mi><mspace></mspace><mtext>and</mtext></mrow></math></span> <span><math><mrow><msub><mi>C</mi><mrow><mi>e</mi><mi>f</mi><mi>f</mi><mn>2</mn></mrow></msub><mo>=</mo><mn>7.87</mn><mo>∗</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>8</mn></mrow></msup><mspace></mspace><mi>F</mi></mrow></math></span>, with corresponding relaxation times of approximately <span><math><mrow><msub><mi>τ</mi><mrow><mi>e</mi><mi>f</mi><mi>f</mi><mn>1</mn></mrow></msub><mo>=</mo><mn>1.12</mn><mo>∗</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>6</mn></mrow></msup><mspace></mspace><mi>s</mi><mspace></mspace><mtext>and</mtext><mspace></mspace><msub><mi>τ</mi><mrow><mi>e</mi><mi>f</mi><mi>f</mi><mn>2</mn></mrow></msub><mo>=</mo><mn>3.6</mn><mo>∗</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>5</mn></mrow></msup><mspace></mspace><mi>s</mi></mrow></math></span> respectively. The observed low-frequency nonlinear dielectric response exhibits strong dependence on the applied DC bias, leading to a pronounced decrease in the real part and increase in the imaginary part of the dielectric permittivity. This bias-controlled behavior suggests great potential for implementation in tunable capacitors and frequency-dependent energy storage components. The obtained results demonstrate the interplay between conduction and polarization processes in nanostructured carbon films and validate the relevance of the cluster-based structural model.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"727 ","pages":"Article 418322"},"PeriodicalIF":2.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146081276","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 structure correction and strained optimized physical aspects of the Ca2TiRuO6","authors":"Huda A. Alburaih ,&nbsp;Samia Shahzadi ,&nbsp;Muhammad Mushtaq ,&nbsp;S. Nazir","doi":"10.1016/j.physb.2026.418348","DOIUrl":"10.1016/j.physb.2026.418348","url":null,"abstract":"<div><div>We explore the numerous physical aspects of the newly synthesized Ca<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>TiRuO<span><math><msub><mrow></mrow><mrow><mn>6</mn></mrow></msub></math></span> system using <em>ab-initio</em> calculations. The structure is thermodynamically and mechanically stable, as verified by formation/cohesive energetics and elastic tensors, respectively. The material is ductile in nature and maintains the ionic bonding. Alongside, a stable ferromagnetic semiconducting state with an energy band gap (<span><math><msub><mrow><mi>E</mi></mrow><mrow><mi>g</mi></mrow></msub></math></span>) of 0.90 eV is found, which is in excellent agreement with the experiment with an accuracy of 98.9%. The magnetic moment on the Ru ion is 1.63 <span><math><msub><mrow><mi>μ</mi></mrow><mrow><mi>B</mi></mrow></msub></math></span> with S = 1, which is confirmed by a three-dimensional spin-magnetization density plot. Further, the <span><math><msub><mrow><mi>E</mi></mrow><mrow><mi>g</mi></mrow></msub></math></span> varies between 0.64/0.54 to 0.98/1.06 eV for the <span><math><mo>−</mo></math></span>5% and ＋5% biaxial ([110])/hydrostatic ([111]) strains, respectively. A small variation in the Ru spin-moment is also observed against strain. Finally, the Bader charge examination proved that mixed ionic and covalent aspects are due to complex chemical bonding.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"727 ","pages":"Article 418348"},"PeriodicalIF":2.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146171004","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 magnetic and Hall transport phenomena in XCuVZ (X = Fe, Co, Ni; Z = Al, Sn, Sb) equiatomic quaternary Heusler compounds","authors":"Jen-Chuan Tung ,&nbsp;Chi-Hsuan Lee ,&nbsp;Chun-Hsien Lee ,&nbsp;Po-Liang Liu","doi":"10.1016/j.physb.2026.418349","DOIUrl":"10.1016/j.physb.2026.418349","url":null,"abstract":"<div><div>We present a first-principles study of equiatomic quaternary Heusler compounds XCuVZ (X = Fe, Co, Ni; Z = In, Sn, Sb), focusing on structural, magnetic, and Hall transport properties. Three crystallographic configurations were examined. Type I configurations stabilize either ferromagnetic or antiferromagnetic states, while Type II and III structures exhibit diverse behaviors including antiferromagnetic, ferrimagnetic, half-metallic, and nonmagnetic phases. Spin moment analysis reveals Fe and Co as the main contributors, with V often carrying negative spin moments that promote spin compensation. Spin–orbit coupling was included to evaluate anomalous and spin Hall conductivities via Wannier interpolation. We found that CoCuVSb (Type II) approaches half-metallicity with an integer magnetic moment and a spin-down gap, underscoring its potential for spintronics. Overall, our results highlight the decisive role of atomic ordering and substitution in tailoring ferromagnetic, ferrimagnetic, and antiferromagnetic ground states, as well as their transport responses in Heusler compounds.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"727 ","pages":"Article 418349"},"PeriodicalIF":2.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146171008","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":"Strain-induced modulation of conductance and spin transfer torque in graphene spin valves","authors":"Ayat Javadpour,&nbsp;Babak Abdollahipour","doi":"10.1016/j.physb.2026.418352","DOIUrl":"10.1016/j.physb.2026.418352","url":null,"abstract":"<div><div>We investigate how uniaxial strain influences conductance and spin-transfer torque in graphene spin-valve systems under an external magnetic field. Both uniform and nonuniform strains are applied to the normal graphene segment alongside a gate potential. By solving the junction Hamiltonian and matching wave functions across normal–ferromagnetic interfaces, we obtain the transmission coefficients and calculate the conductance and spin transfer torque. Our results show that strain modifies the periodicity of conductance and spin-transfer torque oscillations with respect to gate potential, enabling control of oscillation periods through strain strength. The magnetic field enhances conductance in the parallel configuration while suppressing it in the antiparallel case, and introduces a threshold potential for nonzero conductance at high fields. Moreover, the magnetic field drives spin-transfer torques from an asymmetric to a symmetric state relative to angle between magnetizations of the ferromagnetic contacts. These findings highlight strain and magnetic field as effective tools for fine-tuning the electronic and spintronic properties of graphene spin-valve junctions.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"727 ","pages":"Article 418352"},"PeriodicalIF":2.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146170947","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":"Interface engineering of Schottky contacts in 2D VX2/SiS2 (X = S, Se) heterostructures via strain and electric field: manipulating barrier height and quantum tunneling behavior","authors":"You Xie,&nbsp;Jiahao Wang,&nbsp;Zhengyong Chen,&nbsp;Yan Chen,&nbsp;Huaze Zhu,&nbsp;Tao Zhang","doi":"10.1016/j.physb.2026.418331","DOIUrl":"10.1016/j.physb.2026.418331","url":null,"abstract":"<div><div>First-principles calculations systematically investigate the structural stability, electronic properties, and contact behavior of two-dimensional van der Waals heterostructures (vdWHs) composed of metallic VS₂ (or VSe₂) and semiconducting SiS₂ monolayers. Both VS₂/SiS₂ and VSe₂/SiS₂ vdWHs exhibit excellent stability with low lattice mismatch and negative binding energy. VS₂/SiS₂ forms an n-type Schottky contact (barrier height of 0.38 eV), while VSe₂/SiS₂ shows a near-Ohmic contact (0.08 eV). Quantum tunneling reveals a significant interfacial barrier (∼4.5 % probability). Vertical strain and external electric fields effectively modulate the Schottky barrier height, tunneling probability, and metal-induced gap states. Compressive strain enhances interfacial coupling, while tensile strain suppresses it. Electric fields enable continuous, reversible contact tuning, even inducing Schottky-to-Ohmic transitions, with VSe₂/SiS₂ exhibiting greater tunability. This work provides insights and a design basis for tunable 2D electronic devices.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"727 ","pages":"Article 418331"},"PeriodicalIF":2.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146081272","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":"Impact of Ga2O3 doping on microstructure and electrical properties of novel ZnO-MnO2-SrCO3-based linear resistors","authors":"Xuefang Chen ,&nbsp;Lingru Meng ,&nbsp;Yunong Liao ,&nbsp;Weiqi Zhang ,&nbsp;Jinyi Wu ,&nbsp;Ruiqing Chu ,&nbsp;Zhijun Xu","doi":"10.1016/j.physb.2026.418314","DOIUrl":"10.1016/j.physb.2026.418314","url":null,"abstract":"<div><div>In this study, Ga₂O₃ doped ZnO-MnO₂-SrCO₃-based linear resistors were prepared through a sintering process at 1320 °C. The impacts of Ga₂O₃ doping on the microstructure and electrical properties of the ZnO-based linear resistors were systematically investigated. The results show that doping with a moderate amount of Ga₂O₃ promotes the growth of ZnO grains, effectively reduces the nonlinear coefficient of resistors and enhances the resistance frequency stability. It also enables the resistivity of the resistors to be adjusted over a wide range. The nonlinear coefficient (α) of the resistor reaches 1.0 when 0.3 mol% Ga₂O₃ is doped. The resistivity (ρ) reaches the smallest value of 855.31 Ω cm when the 0.5 mol% Ga₂O₃ is doped. It is about 98.6 % lower than the value at a doping concentration of 0.1 mol% Ga₂O₃. The doping of Ga₂O₃ not only improves the linearity of ZnO-based resistors, but also reduces their resistivity to some extent.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"727 ","pages":"Article 418314"},"PeriodicalIF":2.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146081200","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":"Prediction of metastable YBH8 phases with high-Tc superconductivity: A first principle investigation","authors":"Fang-guang Kuang ,&nbsp;Ji-chun Lian ,&nbsp;Xiao-zhen Yan ,&nbsp;Chuan-zhao Zhang ,&nbsp;Jia-xin Dong ,&nbsp;Wen-ming kang ,&nbsp;Shu-ying Kang","doi":"10.1016/j.physb.2026.418288","DOIUrl":"10.1016/j.physb.2026.418288","url":null,"abstract":"<div><div>Through an integrated computational approach combining first-principles calculations and crystal structure prediction, we conduct a comprehensive investigation of superconducting mechanisms in YBH₈ across its potential high-pressure polymorphs. Our study elucidates the intricate relationship between crystal symmetry, electronic structure, and electron-phonon coupling (EPC) in determining superconductive properties. The <em>C</em>2/<em>c</em> phase is the most stable above 160 GPa, while the <em>I</em>4/<em>mmm</em> and <em>Fm</em>—3<em>m</em> phases exhibit strong electron-phonon coupling and high densities of states at the Fermi level, leading to predicted superconducting critical temperatures (<em>T</em>_<em>c</em>) of 144–165 K. Our analysis highlights the critical role of crystal symmetry and BH_n unit configuration in achieving high-<em>T</em>_<em>c</em> superconductivity. These results establish <em>I</em>4/<em>mmm</em> and <em>Fm</em>—3<em>m-</em>YBH₈ as promising superconducting candidates and provide a rational framework for extending such principles to other rare-earth borohydrides.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"727 ","pages":"Article 418288"},"PeriodicalIF":2.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146081201","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":"Splitting of the photonic bands in one-dimensional bi- and multi-periodic dielectric-graphene based photonic crystals","authors":"A. Sánchez-Arellano ,&nbsp;D. Ariza-Flores ,&nbsp;J.S. Pérez-Huerta ,&nbsp;S. Amador-Alvarado ,&nbsp;I.A. Sustaita-Torres ,&nbsp;J. Madrigal-Melchor","doi":"10.1016/j.physb.2026.418318","DOIUrl":"10.1016/j.physb.2026.418318","url":null,"abstract":"<div><div>One-dimensional graphene-based photonic crystals have been identified as a promising solution for active terahertz wave tuning. However, conventional designs are constrained by the limitations of strict periodicity and uniform chemical potential distribution. The present study proposes a novel <em>multi-periodic</em> structure that introduces controlled variations in both the graphene chemical potential and the number of graphene layers within the unit cell. This intracell modulation, characterized by non-uniform doping, gives rise to the significant physical phenomenon of photonic band splitting. The numerical analysis was performed using the Transfer Matrix Method. Results demonstrate that the band structure splits, modifying both the number and the widths of the photonic band gaps compared to the corresponding uniform photonic crystal. Band splitting is directly correlated with the internal variations in the unit cell, enabling precise spectral engineering. These findings provide a robust framework for designing next-generation tunable multi-channel filters, optical switches, and highly tunable sensing devices.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"727 ","pages":"Article 418318"},"PeriodicalIF":2.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146081277","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":"DFT and AIMD insights into the photo-excited stability of Na2ReXO6 (X=Al, In) perovskites for efficient energy harvesting","authors":"Sanober Kanwal ,&nbsp;Ahsan Illahi ,&nbsp;Amna Nasir ,&nbsp;Asif Nawaz Khan ,&nbsp;M. Anis-ur-Rehman ,&nbsp;Muhammad Kaleem","doi":"10.1016/j.physb.2026.418309","DOIUrl":"10.1016/j.physb.2026.418309","url":null,"abstract":"<div><div>Perovskite oxides have been extensively studied for optoelectronic applications because of their flexible structure. In this work utilizing the FP-LAPW method in the Wien2K code to examine the double perovskites Na₂ReXO₆ (X = Al, In) for efficient energy harvesting devices. The structures were relaxed using Perdew-Burke-Ernzerhof (PBE) method's Generalized Gradient Approximation (GGA) and the Tran-Blaha modified Becke-Johnson (TB-mBJ) scheme was employed for accurate electronic properties. Both compounds are structurally and thermodynamically stable, and thermal stability of both compounds was demonstrated through AIMD simulations. These compounds exhibit mechanical stability and the absence of negative frequencies in the phonon dispersion curves confirms their dynamically stability. Analysis of the band structure revealed that the Na₂ReXO₆ (X = Al, In) perovskites exhibit direct bandgap of 1.243 eV and 1.741 eV respectively. Additionally, significant dielectric response and high absorption coefficients of Na₂ReXO₆ (X = Al, In) make these compounds optically active in the visible spectrum suggesting their potential for energy harvesting.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"727 ","pages":"Article 418309"},"PeriodicalIF":2.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146081274","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":"Tuning magnetic properties and anomalous Hall effect in Kagome ferromagnet Fe3Sn2 via Ge doping","authors":"Chen Liu ,&nbsp;Zhongquan Mao ,&nbsp;Jiang Zhang ,&nbsp;Qinglin Jiang","doi":"10.1016/j.physb.2026.418366","DOIUrl":"10.1016/j.physb.2026.418366","url":null,"abstract":"<div><div>The Kagome-lattice ferromagnet Fe₃Sn₂ exhibits room-temperature ferromagnetism and strong Berry-curvature-driven transport phenomena, making it a promising platform for topological spintronics. In this work, we synthesized Fe₃Sn₂ and Ge-doped variants Fe₃Sn_1.98Ge_0.02 and Fe₃Sn_1.95Ge_0.05 to investigate the effects of Ge substitution on its magnetic and electronic transport properties. X-ray diffraction results confirm phase purity and structural stability across all samples. Magnetic measurements show a reduction in saturation magnetization with increasing Ge content, indicating the suppressed magnetic ordering via doping. Transport measurements reveal that doping improved conductivity and carrier mobility. Anomalous Hall effect analysis indicates that doping shifts it from multi-band to hole-dominated transport, with a decrease in the anomalous Hall coefficient but an increase in the Hall scaling factor, implying enhanced intrinsic (Berry curvature) contributions. These findings demonstrate that Ge doping offers an effective way to tune the magnetic and topological transport properties of Fe₃Sn₂.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"727 ","pages":"Article 418366"},"PeriodicalIF":2.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146171001","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}