Journal of Physics: Condensed Matter最新文献

{"title":"On-surface C-C coupling reactivity of carbon atoms in halogenated azulene.","authors":"Wenxun Feng, Yanbo Li, Jianmin Huang, Junlong Ma, Xisha Zhang, Deqing Zhang, Qitang Fan, Bing Wang","doi":"10.1088/1361-648X/adc35c","DOIUrl":"10.1088/1361-648X/adc35c","url":null,"abstract":"<p><p>Azulene molecule, consisting of a pair of five and seven-membered rings, represents a promising precursor for the on-surface synthesis of nonbenzenoid, nonalternant carbon nanostructures with exotic properties. However, controlling the selective C-C coupling between azulene molecules remains elusive, undermining the structural uniformity of the attained carbon nanostructures. Here, we report that the on-surface C-C coupling reactivity of different carbon atom sites in azulene relies on the spatial distribution of its frontier orbitals. By performing surface reactions of a tribrominated azulene molecule on Au(111), the probability of C-C coupling between carbon atoms at different sites of azulene has been revealed by scanning tunneling microscopy and non-contact atomic force microscopy. These findings are in accordance with the density functional theory-calculated energy barriers for the corresponding C-C coupling reaction steps.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143670186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Defects in oxide ultrathin films and 2D materials.","authors":"Falko P Netzer, Svetlozar Surnev","doi":"10.1088/1361-648X/adc05f","DOIUrl":"10.1088/1361-648X/adc05f","url":null,"abstract":"<p><p>Defects, that are irregularities in crystal lattices, create special sites or regions of particular geometry, electronic structure and activity that influence the physical and chemical behavior of the materials in a significant way. Here we examine published work on defects in two-dimensional (2D) oxide systems. The latter have attracted interest and significance in many areas of modern science and technology in recent years. The defects are classified according to their dimensionality: point defects, line defects and 2D specific topological defects are considered. Key features of the different defect types are illustrated and discussed with selected prototypical examples.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143625036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Signatures of magnon-phonon coupling in frustrated double perovskite square lattices.","authors":"Shalini Badola, Aprajita Joshi, Akriti Singh, Surajit Saha","doi":"10.1088/1361-648X/adc0da","DOIUrl":"10.1088/1361-648X/adc0da","url":null,"abstract":"<p><p>Low-dimensional frustrated magnetic square networks feature a variety of unconventional phases with novel emergent excitations. Often these excitations are intertwined and manifest into intriguing phenomena, an area that has remained largely unexplored in square-lattice systems, especially, double perovskites (A₂BB'O₆). In this study, we explore these interactions between the fundamental excitations such as phonons and magnons in square-lattice Sr₂CuTeO₆, Sr₂CuWO₆, and Ba₂CuWO₆isostructural double perovskites that exhibit both short-ranged (<i>T</i>_max) as well as long-ranged Néel antiferromagnetic (<i>T</i>_N) transitions. Our Raman measurements at variable temperatures reveal an intriguing broad peak (identified as 2-magnon (2M)) surviving beyond<i>T</i>_maxfor W-based compositions contrary to the Te-based system, suggesting a key role of diamagnetic B'-site cation on their magnetism. The thermal response of 2M intriguingly shows signatures of correlation with phonons and control over their anharmonicity, depicting magnon-phonon interaction. Further, a few phonons exhibit anomalies across the magnetic transitions implying the presence of spin-phonon coupling. In particular, the phonon modes at ∼194 cm^-1of Sr₂CuTeO₆and ∼168 cm^-1of Sr₂CuWO₆, that show a strong correlation with the 2M, exhibit the strongest spin-phonon coupling suggesting their roles in mediating magnon-phonon interactions in these systems.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143630342","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Recent progress of flexible electrospun nanofibers based triboelectric nanogenerators for self-powered electronics.","authors":"Han Li, Ziteng Xu, Jiaxun Zhang, Saisai Li, Shuoze Li, Xingwei Chen, Lijun Lu, Zhifeng Pan, Yanchao Mao","doi":"10.1088/1361-648X/adbfed","DOIUrl":"10.1088/1361-648X/adbfed","url":null,"abstract":"<p><p>The depletion of fossil fuels and the environmental impact of chemical batteries, coupled with the rapid proliferation of portable electronic devices and the Internet of Things, have created an urgent demand for high-performance, lightweight, and sustainable energy systems. Flexible triboelectric nanogenerators (TENGs) have emerged as a promising technology for powering self-sufficient devices, offering advantages such as simple structure, flexibility, low cost, and environmental adaptability. In particular, electrospun nanofiber-based TENGs stand out due to their enhanced surface area, superior charge collection capabilities, and improved mechanical durability. This review presents a comprehensive overview of recent advancements in electrospun nanofiber-based TENGs, focusing on material selection, structural design, fabrication techniques, and their integration into applications ranging from self-powered sensors to wearable electronics. Furthermore, the review discusses the challenges and future directions in optimizing the performance and scalability of TENGs to meet the growing demands of next-generation, energy-efficient technologies. It is hoped that this review will help researchers to gain a deeper understanding of this field and promote its development to a new stage.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143615781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Robust half-metallic properties in two-dimensional CuCr₂Se₂X₂(X = Cl, Br, I).","authors":"Haimei Zhou, Yujing Guo, Shuai Liu, Yiran Peng, Wenhui Wan, Yong Liu, Yanfeng Ge","doi":"10.1088/1361-648X/adbeb0","DOIUrl":"10.1088/1361-648X/adbeb0","url":null,"abstract":"<p><p>In recent years, the rapid development of two-dimensional (2D) magnetic materials has revolutionized the field of spintronics, driven by their unique ability to combine magnetism and electronic functionality at the atomic scale. Here, we investigate the monolayer CuCr₂Se₂X₂(X = Cl, Br, I), which exhibit robust ferromagnetic (FM) behavior and half-metallicity with 100% spin polarization. The strong FM coupling, mediated by superexchange interactions, is rooted in the unique electronic structure of the Cr<i>d</i>-orbitals. Our findings reveal high Curie temperatures (TC) exceeding room temperature, with the Br variant achieving a remarkable 586 K. These exceptional properties, including the ability to modulate exchange interactions through strain engineering, highlight CuCr₂Se₂X₂as a versatile platform for flexible, high-performance spintronic devices, paving the way for advancements in next-generation electronic applications.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143597241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Extended Kohler's scaling and Isosbestic point in the charge density wave state of 1T-VSe₂.","authors":"Sonika Bagga, Sunil Gangwar, Pankaj Kumar, Arghya Taraphder, C S Yadav","doi":"10.1088/1361-648X/adc6e4","DOIUrl":"https://doi.org/10.1088/1361-648X/adc6e4","url":null,"abstract":"<p><p>1T-VSe₂is a narrow band transition metal chalcogenide that shows charge density wave (CDW) state below T_CDW= 110 K. Here, we have explored the relevance of Kohler's rule and the thermal transport properties of VSe₂across the CDW state in the presence of magnetic field. The magnetoresistance (MR) follows Kohler's rule above T_CDW, while an extended Kohler's rule is employed below T_CDW. Interestingly, we observed an anomaly in MR around T ∼ 20 K, below which MR value decreases on lowering temperature. This anomaly is also reflected in the slope (κ) of Kohler's plots and the relative change in the thermal excitation induced carrier density (n_T). Despite a strong magnetic field of 14 Tesla, the T_CDWremains largely unaffected in both electrical resistivity (ρ(T)) and Seebeck coefficient (S), although the application of magnetic field does enhance the peak intensity of S around T ∼ 60 K. The crossover of S curves measured at different magnetic fields at T ∼ 20 K suggests the existence of a novel feature within the CDW state of VSe₂i.e., the presence of a locally exact isosbestic point.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143742960","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Positron stopping in multilayer materials.","authors":"A C L Jones, T Chung, F A Selim","doi":"10.1088/1361-648X/adc062","DOIUrl":"10.1088/1361-648X/adc062","url":null,"abstract":"<p><p>Positron annihilation spectroscopy provides a sensitive toolset for defect characterization. In beam based studies of single-layer targets, the form of implantation profiles is well established, depending on the kinetic energy and angle of incident positrons relative to the target surface and the density and average atomic number of the target. For multilayer systems, the difference in density and across the layers makes derivation of an analytical form difficult. To date, the determination of positron stopping profiles in multilayer targets has primarily involved Monte Carlo simulations. We present here an alternative approach that estimates the energy distributiondN/dEof those positrons transmitted past each layer boundary, by fitting the remaining tail of the stopping profile after each layer with a basis set comprised of calculated stopping profiles in the same material they are transmitted through. The stopping profile in the next layer is then found by summing a series of stopping profiles in the new medium in proportion to the determined distributiondN/dE. The results of our model are compared with simulation results in a system of alternating layers of Al and Au and find reasonable agreement in the predicted profile and excellent agreement in the predicted mean implantation depth. Lastly, we derived a simple formula-based approach for the calculation of the mean implantation depth in two-layer systems that provides results in excellent agreement with the full model.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143625039","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 of zinc oxide nano-rice decorated with silver nanoparticles for surface-enhanced Raman scattering (SERS) trace detection of isoprocarb and crystal violet.","authors":"Sy Van Vu, Kim-Dung Thi Ho, Phuong-Thao Do, Thu Anh Nguyen, Quang Duy Nguyen, Trung-Dung Tran Nguyen, Huy Huu Truong, Man Van Tran, Tien Nu Hoang Lo, In Park, Van-Nam Dao, Van-Dung Le, Khuong Quoc Vo","doi":"10.1088/1361-648X/adc05d","DOIUrl":"10.1088/1361-648X/adc05d","url":null,"abstract":"<p><p>Surface-enhanced Raman scattering (SERS) has gained substantial interest for the practical analysis of trace amounts of various molecules. However, improving the magnitude of the electromagnetic enhancement and preparing the substrate for long-term use remains top research priorities. This study presents a novel and straightforward synthesis method for zinc oxide nanorices (ZnONRs) decorated with small silver particles (Ag/ZnONR), which can serve as a highly stable, sensitive, and reproducible material for SERS detection of isoprocarb (IPC) and crystal violet (CV). Integrating ZnONR and AgNPs at an appropriate mixing ratio can generate many plasmonic 'hotspots' on the surface due to the strong surface plasmon capability of AgNPs when excited by appropriate light. The length of ZnO nanorods (ZnONR) has been controlled to range from 100 nm to 120 nm, with an aspect ratio (AR, the ratio of nanoparticle length to width) of about 3:1. Additionally, the formed silver nanoparticles have an average diameter of approximately 20-40 nm and randomly distributed on the surface of the ZnO. Specifically, we found that the exceptional detection enhancement factor was 2.5 × 10⁹, along with high reproducibility due to the embedding of AgNPs in the inert structure of ZnO nano rice, which helps prevent the loss of AgNPs during analysis and can be reused multiple times while maintaining good signal intensity stability. Significantly, this embedded nanostructure could achieve a reasonable limit of detection of 0.402 nM for CV and 0.147 pM for IPC, with a high reproducibility (RSD of 5,98%). The electromagnetic field enhancement phenomenon of this nanomaterial was further analyzed through Finite-Difference Time-Domain simulations, demonstrating that the intensity of the electromagnetic field (EM-field) of Ag/ZnONRs (66.0) is significantly ten times greater than that observed with pristine AgNPs (6.31) or ZnONRs (1.84). Integrating these nanomaterials creates a sophisticated category of hybrid nanosubstrates suitable for a wide range of future detection applications employing the SERS method.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143625053","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Addendum: Microscopic dynamics and Bose-Einstein condensation in liquid helium (2023<i>J. Phys.: Condens. Matter</i>35085101).","authors":"K Trachenko","doi":"10.1088/1361-648X/adc063","DOIUrl":"https://doi.org/10.1088/1361-648X/adc063","url":null,"abstract":"<p><p>We have recently proposed that mobile transit atoms in liquid⁴He accumulate in a finite-energy state, consistent with microscopic dynamics in liquids and different types of experimental data (Trachenko 2023<i>J. Phys.: Condens. Matter</i><b>35</b>085101). Here, we point out that the superfluid transition temperature<i>T</i>_<i>λ</i>can be evaluated in this picture and is found to be within 15% of experimental<i>T</i>_<i>λ</i>.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":"37 18","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143730608","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Structure and dynamics of phytantriol-glycerol mesophases: insights into the reverse micelle to lamellar phase transition.","authors":"Matteo Rutsch, Yang Yao","doi":"10.1088/1361-648X/adbeae","DOIUrl":"10.1088/1361-648X/adbeae","url":null,"abstract":"<p><p>Lipidic mesophases (LMPs) are lyotropic liquid crystals formed by the self-assembly of lipid in water, offering diverse phase symmetries with unique physicochemical properties. However, a fundamental understanding of how the dynamics relate to the composition and structure remains limited. In this study, we substitute water with glycerol, which closely resembles the headgroup structure of phytantriol, as the solvent to explore phytantriol-based LMPs in a pure glycerol environment. The non-crystallizing nature of both phytantriol and glycerol enables phase studies at sub-zero temperatures. Combined small-angle x-ray scattering and differential scanning calorimetry analyses confirm the formation of reverse micelles (<i>L</i>₂), which undergo a phase transition to lamellar phase (<i>L_α</i>) upon cooling. Broadband dielectric spectroscopy (BDS) reveals how the dynamics of phytantriol are governed by the composition and symmetry of the LMP: increased glycerol content decreases the relaxation time of the Debye- and<i>α</i>-relaxation, therefore exerting a plasticizing effect. The change in long-range order of phytantriol during the<i>L</i>₂-<i>L_α</i>phase transition reveals a decrease of the conductivity relaxation time. The introduction of a net orientation of phytantriol further reveals a new relaxation process-the dipole-matrix interaction-exclusive to the<i>L_α</i>phase. Our results highlight the value of combining BDS with structural and thermal analyses for a deeper understanding of the dynamics in soft matter systems.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143597243","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}