Physica B-condensed Matter最新文献

{"title":"Multifunctional Janus altermagnet Ti2OBrI monolayer with coupled magnetic, piezoelectric, and valleytronic properties","authors":"Bing Li ,&nbsp;Busheng Wang ,&nbsp;Qiuyue Ma ,&nbsp;Yong Liu","doi":"10.1016/j.physb.2026.418316","DOIUrl":"10.1016/j.physb.2026.418316","url":null,"abstract":"<div><div>Altermagnetism, as the confirmed third form of collinear magnets, exhibits novel physical properties due to its antiferromagnetic coupling and non-relativistic band spin splitting, offering a route toward multifunctional spintronic and valleytronic devices. Due to strict symmetry constraints, research on two-dimensional altermagnetic materials is relatively scarce. In this study, based on first-principles calculations, we propose a two-dimensional (2D) altermagnetic semiconductor—the Janus Ti₂OBrI monolayer, which exhibits out-of-plane magnetic anisotropy and an high Néel temperature. The system hosts large spin splitting (1.18 eV) and a pair of Dirac-type valleys at the time-reversal-invariant <span><math><mi>X</mi></math></span> and <span><math><mi>Y</mi></math></span> points, connected by crystal rather than time-reversal symmetry. Breaking this symmetry via uniaxial strain induces valley polarization and inversion, leading to a strain-driven piezoelectric valley effect. Additionally, moderate hole doping generates a net magnetization through a piezomagnetic coupling mechanism. These findings reveal Ti₂OBrI as a prototype 2D altermagnet that unifies magnetism, piezoelectricity, and valleytronics within a single monolayer crystal.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"728 ","pages":"Article 418316"},"PeriodicalIF":2.8,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146172744","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":"Highly efficient and thermally tunable VO2-based square-slotted passive radiative cooler for high temperature applications","authors":"Muhammad Faizan ,&nbsp;Muhammad Abuzar Baqir ,&nbsp;Muhammad Saqlain ,&nbsp;Zaid Ahmed Shamsan","doi":"10.1016/j.physb.2026.418380","DOIUrl":"10.1016/j.physb.2026.418380","url":null,"abstract":"<div><div>Passive radiative cooling (PRC) is an emerging technology that effectively lowers the temperature of the object without power consumption. Recently, metamaterials have emerged as a focal point for research and development due to their application in PRC devices. The capability to radiate excess heat within the atmospheric thermal windows (8-13 μm) to outer space contributes to an overall cooling effect in the surrounding environment. This study proposes a PRC device utilizing a thermally controllable VO₂ metasurface grown over a MgF₂ dielectric layer. The device exhibits elevated emissivity (of 98.5%) within the atmospheric window under high operating temperature conditions. Furthermore, the results indicate a net cooling power of 143.9 W/m² at a VO₂ temperature of 90 °C, in the absence of solar radiation, leading to a temperature drop of ∼11.0K relative to ambient. However, for low operating temperatures, VO₂ emissivity drastically decreases within the atmospheric window and reaches a minimal value of 4.42% at 30 °C, in the absence of direct solar heating. The developed PRC structure would be suitable for high-temperature applications, including data centers, electronic systems, and spacecraft cores, where effective thermal management is crucial.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"728 ","pages":"Article 418380"},"PeriodicalIF":2.8,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146172796","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-temperature superconductivity in compressed molecular hydrogen via controlled electron-doping","authors":"Ashok K. Verma ,&nbsp;P. Modak","doi":"10.1016/j.physb.2026.418355","DOIUrl":"10.1016/j.physb.2026.418355","url":null,"abstract":"<div><div>We investigate the controlled electron-doping of compressed molecular hydrogen via lithium to achieve high-temperature superconductivity. Using first-principles calculations, we perform variable-composition crystal structure searches under high pressure to identify stable Li-doped molecular hydrogen lattices. Our results reveal a cubic LiH₁₂ phase which exhibits key structural and electronic properties conducive to high-temperature superconductivity. Bader charge analysis shows charge transfer from lithium to hydrogen sublattice, modifying intra- and intermolecular H–H distances and inducing metallization without molecular dissociation. Additionally, lithium ions serve as stabilizers for the distorted H₂ molecular network through ionic bonding. A nearly rigid shift in the electronic band structure and density of states, observed with and without lithium, confirms the electron-doping effects of molecular hydrogen. Anisotropic Migdal–Eliashberg calculations predict superconductivity above room temperature in cubic LiH₁₂ at 250 GPa, a pressure that can be readily achieved in a diamond-anvil cell experiment. Analysis of the Eliashberg function highlights the critical role of low- and intermediate-energy phonons in driving strong electron–phonon coupling.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"728 ","pages":"Article 418355"},"PeriodicalIF":2.8,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146172731","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":"Optical properties of Lu3+ ions at different doping concentrations in Ho:Ba(Y1-xLux)2F8 crystals for 3.9 μm laser application","authors":"Xinyu Wang ,&nbsp;Lele Gao ,&nbsp;Huihui Cao ,&nbsp;Jiawei Guo ,&nbsp;You Wang ,&nbsp;Xuejian Zhang ,&nbsp;Lin Wang ,&nbsp;Yongtao Li ,&nbsp;Yang Yu ,&nbsp;Long Tian ,&nbsp;Jing Feng ,&nbsp;Shuyan Song ,&nbsp;Hongjie Zhang","doi":"10.1016/j.physb.2026.418376","DOIUrl":"10.1016/j.physb.2026.418376","url":null,"abstract":"<div><div>Mid-infrared laser crystal materials face problems such as low laser efficiency and difficulty in growth, and have always been a research hotspot for research teams in various countries. In this paper, monoclinic Ba(Y_1-xLu_x)₂F₈ (Ho:BYLF) crystals were grown by the Bridgman method. With a fixed Ho³⁺ ions doping concentration (30 mol%), different Lu³⁺ ions doping concentrations (x = 0, 5, 10, 20 mol%) were incorporated into Ho:BYF crystals to improve their thermal properties. The results indicate that while the ⁵I₅ energy level lifetime of Ho³⁺ ions is not significantly shortened with Lu³⁺ ions doping, the thermal performance of the crystals is significantly enhanced. Under pumping by an 889 nm laser diode, the emission peaks of Ho³⁺ ions in Ho:BYLF crystals within the wavelength range of 3-5 μm were detected. The spectral parameters of crystals with different doping concentrations were calculated in detail. With increasing Lu³⁺ ions concentration, the absorption cross-section σ_abs exhibits a monotonically decreasing trend [(9.62→7.46→4.29→ 3.61)×10⁻²⁰ cm²], while the emission cross-section σ_emi shows a non-monotonic trend [(17.2→7.57→10.09→9.27)×10⁻²⁰ cm²]. The laser pumping experiments indicate that Ho:BYLF crystals with varying Lu³⁺ ions doping concentrations exhibit relatively low pumping thresholds. However, when the Lu³⁺ concentration is 10 mol%, the Ho:BYLF crystal saturates at a pumping energy of 2.8 mJ. The primary goal of Lu³⁺ ions incorporation is to improve the crystal's thermal stability without significantly affecting Ho³⁺ ions' laser performance. This strategy effectively reduces the risk of thermal damage during high-power laser operations. This optimized Ho:BYLF crystal shows significant potential for mid-infrared laser applications.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"728 ","pages":"Article 418376"},"PeriodicalIF":2.8,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146172730","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":"Effects of blue illumination on the thermoluminescence of amazonite (KAlSi3O8)","authors":"Roberto T.E.K. Martins ,&nbsp;Makaiko L. Chithambo ,&nbsp;Neilo M. Trindade","doi":"10.1016/j.physb.2026.418353","DOIUrl":"10.1016/j.physb.2026.418353","url":null,"abstract":"<div><div>In this work, we report the effects of 470 nm blue-light illumination on the conventional thermoluminescence (TL) as well as the phototransfered thermoluminescence (PTTL) of potassic feldspar (KAlSI₃O₈), commonly known as amazonite. We examined the stability of the PTTL signal over repeated measurements cycles, its dependence on charge-trap populations, dose-response behavior and fading properties. The resulting PTTL glow curve can be divided into three temperature regions: (I) 30°C–175 °C, (II) 175°C–350 °C and (III) 250°C–500 °C. Phototransfer effects were observed predominantly in Regions I and II, indicating that these temperature intervals host the traps most susceptible to optical charge transfer.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"728 ","pages":"Article 418353"},"PeriodicalIF":2.8,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146172789","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":"Experimental and theoretical study of malachite green adsorption on CaSiO3/CuO nano-ceramic adsorbent: Molecular and physicochemical insights","authors":"S.H. Kenawy ,&nbsp;Hassan A. Rudayni ,&nbsp;Fahd A. Nasr ,&nbsp;Aliaa M. Badawy ,&nbsp;Yasser F. Salama ,&nbsp;Eder C. Lima ,&nbsp;Glaydson S. dos Reis ,&nbsp;Moaaz K. Seliem","doi":"10.1016/j.physb.2026.418397","DOIUrl":"10.1016/j.physb.2026.418397","url":null,"abstract":"<div><div>Copper oxide–modified wollastonite (CaSiO₃) was synthesized via a controlled coprecipitation route and assessed as a nano-ceramic adsorbent for malachite green (MG) removal from aqueous media. Adsorption behavior was evaluated using conventional kinetic and isotherm models coupled with statistical physics analysis to elucidate molecular-scale mechanisms. The adsorption process followed pseudo-first-order kinetics, while the Liu isotherm best described equilibrium data, yielding maximum capacities of 103.75–117.11 mg/g. Statistical physics modeling indicated a multi-docking adsorption mechanism, with steric parameter values (n = 0.39–0.78) suggesting predominantly horizontal alignment of MG molecules on the adsorbent surface. Increasing temperature enhanced both active site density and saturation capacity, confirming the endothermic nature of adsorption. Low adsorption energies (1.26–3.42 kJ/mol) demonstrated that physisorption dominated, driven mainly by electrostatic and van der Waals interactions. Thermodynamic parameters confirmed the spontaneous nature of MG uptake. The developed ceramic adsorbent exhibited excellent stability and reusability over five adsorption-desorption cycles.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"728 ","pages":"Article 418397"},"PeriodicalIF":2.8,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146172742","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":"Experimental and first-principles study of thermal conductivity in GaN","authors":"Zhengtang Yang ,&nbsp;Qiubo Li ,&nbsp;Zhongxin Wang ,&nbsp;Shouzhi Wang ,&nbsp;Lihuan Wang ,&nbsp;Jinpeng Yang ,&nbsp;Chen-Chang Chen ,&nbsp;Xiaojun Yu ,&nbsp;Yaocheng Liu ,&nbsp;Zhanguo Qi ,&nbsp;Jiachen Du ,&nbsp;Qingbin Liu ,&nbsp;Xiangang Xu ,&nbsp;Lei Zhang","doi":"10.1016/j.physb.2026.418372","DOIUrl":"10.1016/j.physb.2026.418372","url":null,"abstract":"<div><div>This study measures the thermal diffusivity and specific heat capacity at constant pressure of gallium nitride (GaN) within the temperature range of 298 K-523 K, and subsequently calculates the thermal conductivity along the c-axis for three GaN single crystals: unintentionally doped GaN (U-GaN), Fe-doped semi-insulating (SI-GaN), and Si-doped N-type GaN (N-GaN). The thermal conductivity of the U-GaN sample exhibits a T^−1.02 dependence, reaching approximately 175 W/m K at 298 K. SI-GaN samples follow a T^−0.80 relationship with a value of 103 W/m K at room temperature, whereas N-GaN samples scale as T^−0.98 with 120 W/m K at 298 K. The thermal conductivities of the three samples follow the order: U-GaN &gt; N-GaN &gt; SI-GaN. First-principles calculations show that dopant atoms disrupt phonon coherence and induce impurity scattering. In particular, Fe, as a deep-level impurity substantially degrades thermal conductivity.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"728 ","pages":"Article 418372"},"PeriodicalIF":2.8,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146172790","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":"Molecular dynamics investigation of twin boundary effects on the local plasticity of FeNiCrCoCu high-entropy alloy during nanoindentation","authors":"Shuaibo Zhang ,&nbsp;Shanming Fan ,&nbsp;Wenchao Yu ,&nbsp;Jun Li ,&nbsp;Mingjun Peng","doi":"10.1016/j.physb.2026.418370","DOIUrl":"10.1016/j.physb.2026.418370","url":null,"abstract":"<div><div>This molecular dynamics study investigates the nanoindentation response and deformation mechanisms of an equiatomic FeNiCrCoCu high-entropy alloy, with emphasis on the influence of twin boundary spacing and crystal orientation. A critical twin boundary spacing of 3.674 nm is identified, above which classical Hall-Petch strengthening prevails, with hardness increasing as spacing decreases. Below this threshold, an inverse Hall-Petch relationship emerges, attributed to a transition in twin boundary behavior from dislocation barriers to active dislocation emission sources, accompanied by twin boundary migration. This transformation activates cooperative softening mechanisms, including twin partial slip (TPS) and parallel slip transmission along twin boundaries (PSPTB). Crystal orientation governs slip band development and strain localization, while dislocation interactions and twin boundary-mediated processes competitively influence hardening and softening. The results provide insight into the critical spacing-dependent transition between Hall-Petch and inverse Hall-Petch behavior in nanotwinned high-entropy alloys.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"728 ","pages":"Article 418370"},"PeriodicalIF":2.8,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146172784","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":"Optical properties of anisotropic quantum dots: Effects of shape and magnetic field","authors":"Diana Dahliah ,&nbsp;Ayham Shaer ,&nbsp;Esin Kasapoglu","doi":"10.1016/j.physb.2026.418388","DOIUrl":"10.1016/j.physb.2026.418388","url":null,"abstract":"<div><div>This study explores the behavior of an electron in an anisotropic two-dimensional InAs quantum dot under an external magnetic field. The analysis focuses on the energy spectrum and on determining absorption coefficient and refractive index change. To solve the Schrödinger equation of the system, the Hamiltonian is rewritten in terms of rotated coordinates, and the energy spectrum is obtained analytically. For calculating the absorption coefficient and the refractive index change, the standard density matrix formalism combined with the perturbation expansion method is employed.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"728 ","pages":"Article 418388"},"PeriodicalIF":2.8,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146172444","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":"Dual-parameters tunable broadband THz absorber using hybrid graphene-Dirac Semimetal metamaterial structure","authors":"Leiyu Li,&nbsp;Fang Chen,&nbsp;Wenxing Yang","doi":"10.1016/j.physb.2026.418358","DOIUrl":"10.1016/j.physb.2026.418358","url":null,"abstract":"<div><div>A dual dynamically tunable, polarization-insensitive, angle-stable broadband terahertz absorber with a multi-layer metamaterial structure was designed. CST simulations show it achieves &gt;90 % absorption in 2.20-7.00 THz (effective bandwidth 4.80 THz, fractional bandwidth 95.83 %) with six absorption peaks (&gt;98 % absorption). This is achieved through free-space impedance matching. Broadband absorption stems from synergistic multi-layer localized surface plasmon resonance (LSPR) and material loss, and it maintains &gt;90 % absorption for TE and TM polarizations, this absorber has great potential for miniaturized broadband THz devices.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"728 ","pages":"Article 418358"},"PeriodicalIF":2.8,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146172772","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}