Pub Date : 2024-10-01DOI: 10.1016/j.rinp.2024.107981
{"title":"Corrigendum to “Investigation of structural and physical properties of Eu3+ ions substituted Ni0.4Cu0.2Zn0.4Fe2O4 spinel ferrite nanoparticles prepared via sonochemical approach” [Res. Phys. 17 (2020) 103061]","authors":"","doi":"10.1016/j.rinp.2024.107981","DOIUrl":"10.1016/j.rinp.2024.107981","url":null,"abstract":"","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142358734","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-01DOI: 10.1016/j.rinp.2024.107998
Periodically Poled Piezoelectric Film (P3F) stacks have recently been reported as a promising platform for next-generation radio-frequency acoustic filters that extend into cm- and mm-wave bands. By demonstrating the potential for developing high-performance acoustic devices with frequencies up to 20 GHz, P3F structures based on lithium niobate (LiNbO3) films have opened up new possibilities. In this study, the influence of key parameters such as the number of layers, crystal orientation, duty factor, and variation in thicknesses between the layers on the efficiency of the n-th harmonic excitation and spurious modes was examined. To enhance higher-order harmonics, which are suppressed in P3F structures, a novel multilayered stack with Aperiodically Polarized Piezoelectric Films (APPF) is proposed. Optimizing the ratio between layer thicknesses can enhance higher-order harmonics. An optimization principle is described and illustrated by examples of three-layered APPF structures optimized for the generation of antisymmetric Lamb wave harmonics A3-A17, with electromechanical coupling continuously decreasing with frequency. High-frequency modes excited in APPF structures fill the gaps in frequencies and electromechanical coupling coefficients between the modes generated in P3F stacks and can provide greater diversity of device performance.
{"title":"Enhancement of high-frequency harmonics in resonators using multilayered structures with polarity-inverted layers","authors":"","doi":"10.1016/j.rinp.2024.107998","DOIUrl":"10.1016/j.rinp.2024.107998","url":null,"abstract":"<div><div>Periodically Poled Piezoelectric Film (P3F) stacks have recently been reported as a promising platform for next-generation radio-frequency acoustic filters that extend into cm- and mm-wave bands. By demonstrating the potential for developing high-performance acoustic devices with frequencies up to 20 GHz, P3F structures based on lithium niobate (LiNbO3) films have opened up new possibilities. In this study, the influence of key parameters such as the number of layers, crystal orientation, duty factor, and variation in thicknesses between the layers on the efficiency of the n-th harmonic excitation and spurious modes was examined. To enhance higher-order harmonics, which are suppressed in P3F structures, a novel multilayered stack with Aperiodically Polarized Piezoelectric Films (APPF) is proposed. Optimizing the ratio between layer thicknesses can enhance higher-order harmonics. An optimization principle is described and illustrated by examples of three-layered APPF structures optimized for the generation of antisymmetric Lamb wave harmonics A3-A17, with electromechanical coupling continuously decreasing with frequency. High-frequency modes excited in APPF structures fill the gaps in frequencies and electromechanical coupling coefficients between the modes generated in P3F stacks and can provide greater diversity of device performance.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-26DOI: 10.1016/j.rinp.2024.107986
This article analyzes the analytic and solitary wave solutions of the one-dimensional Zabolotskaya-Khokholov (ZK) dynamical model which provides information about the propagation of sound beam or confined wave beam in nonlinear media and studies of beam deformation. By the Lie symmetry analysis method, we acquire the vector fields, commutation relations, optimal system, reduction, and analytic solutions to the specified equation by exerting the Lie group method. Moreover, the solitary wave solutions of the ZK model are procured by exerting the new auxiliary equation method (NAEM). The behavior of the acquired outcomes for several cases is exhibited graphically through two and three-dimensional dynamical wave profiles. Furthermore, the conservation laws of the ZK model are acquired by Ibragimov’s new conservation theorem.
{"title":"Lie symmetry analysis, traveling wave solutions and conservation laws of a Zabolotskaya-Khokholov dynamical model in plasma physics","authors":"","doi":"10.1016/j.rinp.2024.107986","DOIUrl":"10.1016/j.rinp.2024.107986","url":null,"abstract":"<div><div>This article analyzes the analytic and solitary wave solutions of the one-dimensional Zabolotskaya-Khokholov (ZK) dynamical model which provides information about the propagation of sound beam or confined wave beam in nonlinear media and studies of beam deformation. By the Lie symmetry analysis method, we acquire the vector fields, commutation relations, optimal system, reduction, and analytic solutions to the specified equation by exerting the Lie group method. Moreover, the solitary wave solutions of the ZK model are procured by exerting the new auxiliary equation method (NAEM). The behavior of the acquired outcomes for several cases is exhibited graphically through two and three-dimensional dynamical wave profiles. Furthermore, the conservation laws of the ZK model are acquired by Ibragimov’s new conservation theorem.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142327765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-24DOI: 10.1016/j.rinp.2024.107990
Nanotechnology has garnered significant attention for its wide-ranging applications in biomedicine, energy, and environmental science. The synthesis of nanomaterials with specific properties is crucial for advancing these fields. Among various methods, thermal treatment has emerged as a promising technique for producing diverse nanostructures. However, thermal treatment alone often leads to larger particle sizes and poor uniformity, limiting the practical applications of the resulting nanomaterials. Incorporating polyvinylpyrrolidone (PVP) as a capping agent addresses these challenges by reducing particle size and enhancing uniformity. Optimizing parameters such as PVP concentration, molecular weight, temperature, and precursor ratios is key to improving the performance of the PVP-assisted thermal treatment method. This paper reviews recent progress in synthesizing nanostructures using PVP-assisted thermal treatment, including key characterization techniques. It also examines the applications of these nanostructures in fields such as biomedicine, energy, and environmental science. The review identifies challenges in the synthesis and characterization process, while also outlining potential future directions for enhancing this method. The insights provided will be valuable to researchers working in nanotechnology and related disciplines.
{"title":"Recent advances in PVP-assisted thermal treatment: Impact on nanostructure properties, potential applications, challenges, and future perspectives","authors":"","doi":"10.1016/j.rinp.2024.107990","DOIUrl":"10.1016/j.rinp.2024.107990","url":null,"abstract":"<div><div>Nanotechnology has garnered significant attention for its wide-ranging applications in biomedicine, energy, and environmental science. The synthesis of nanomaterials with specific properties is crucial for advancing these fields. Among various methods, thermal treatment has emerged as a promising technique for producing diverse nanostructures. However, thermal treatment alone often leads to larger particle sizes and poor uniformity, limiting the practical applications of the resulting nanomaterials. Incorporating polyvinylpyrrolidone (PVP) as a capping agent addresses these challenges by reducing particle size and enhancing uniformity. Optimizing parameters such as PVP concentration, molecular weight, temperature, and precursor ratios is key to improving the performance of the PVP-assisted thermal treatment method. This paper reviews recent progress in synthesizing nanostructures using PVP-assisted thermal treatment, including key characterization techniques. It also examines the applications of these nanostructures in fields such as biomedicine, energy, and environmental science. The review identifies challenges in the synthesis and characterization process, while also outlining potential future directions for enhancing this method. The insights provided will be valuable to researchers working in nanotechnology and related disciplines.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142322193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-24DOI: 10.1016/j.rinp.2024.107987
Graphene is of particular interest in optoelectronics due to its remarkable transport properties. We analyze the photonic spin Hall effect (PSHE) of a light beam reflected from a layered structure of graphene in its current-carrying state. The relativistic effects arising due to the motion of massless Dirac electrons in graphene greatly influence the transverse displacements of light induced by PSHE. The mentioned effect is studied with different drifting speeds of the charged particles in graphene as well as different thicknesses of the graphene sheet. The substrate on which the graphene is deposited is also shown to play a vital role in manipulating this relativistic PSHE. This study provides a platform for efficient light-matter interaction in which the medium is a current-carrying graphene channel.
{"title":"Probing photonic spin Hall effect with Fizeau drag in graphene","authors":"","doi":"10.1016/j.rinp.2024.107987","DOIUrl":"10.1016/j.rinp.2024.107987","url":null,"abstract":"<div><div>Graphene is of particular interest in optoelectronics due to its remarkable transport properties. We analyze the photonic spin Hall effect (PSHE) of a light beam reflected from a layered structure of graphene in its current-carrying state. The relativistic effects arising due to the motion of massless Dirac electrons in graphene greatly influence the transverse displacements of light induced by PSHE. The mentioned effect is studied with different drifting speeds of the charged particles in graphene as well as different thicknesses of the graphene sheet. The substrate on which the graphene is deposited is also shown to play a vital role in manipulating this relativistic PSHE. This study provides a platform for efficient light-matter interaction in which the medium is a current-carrying graphene channel.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142327766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-24DOI: 10.1016/j.rinp.2024.107992
In response to the growing demand for high-performance magnesium alloys in the aerospace and transportation industries, researchers conducted a study on the AZ80 magnesium alloy. The primary objective was to achieve a nanocrystalline structure in the alloy through severe plastic deformation using low-strain multi-directional compression at room temperature. Subsequently, an aging treatment was performed to induce the transformation of the structure into a stable state. The study aimed to investigate the morphology and mode of the second phase precipitation in the magnesium alloy after undergoing severe plastic deformation. The research findings revealed that the application of multi-directional and multi-pass compression during room temperature deformation of the magnesium alloy effectively prevented instability and fracture. Moreover, this process facilitated the accumulation of larger true strain. As the number of compression passes increased, deformation twins became increasingly denser, particularly in the intersecting areas. Consequently, ultrafine high-angle grain structures were preferentially formed in these regions. Furthermore, the number of fine-grained areas gradually increased with each deformation pass. After ΣΔε 5.12, the grain size was refined to a range of 100–200 nm. Additionally, the aging treatment following severe plastic deformation brought about a significant change in the traditional lamellar precipitation mode of the second phase Mg17Al12 in the magnesium alloy. Instead, spherical precipitation occurred.
{"title":"Nanocrystallization and precipitation behavior evolution of AZ80 magnesium alloy during multi-directional compression","authors":"","doi":"10.1016/j.rinp.2024.107992","DOIUrl":"10.1016/j.rinp.2024.107992","url":null,"abstract":"<div><div>In response to the growing demand for high-performance magnesium alloys in the aerospace and transportation industries, researchers conducted a study on the AZ80 magnesium alloy. The primary objective was to achieve a nanocrystalline structure in the alloy through severe plastic deformation using low-strain multi-directional compression at room temperature. Subsequently, an aging treatment was performed to induce the transformation of the structure into a stable state. The study aimed to investigate the morphology and mode of the second phase precipitation in the magnesium alloy after undergoing severe plastic deformation. The research findings revealed that the application of multi-directional and multi-pass compression during room temperature deformation of the magnesium alloy effectively prevented instability and fracture. Moreover, this process facilitated the accumulation of larger true strain. As the number of compression passes increased, deformation twins became increasingly denser, particularly in the intersecting areas. Consequently, ultrafine high-angle grain structures were preferentially formed in these regions. Furthermore, the number of fine-grained areas gradually increased with each deformation pass. After ΣΔε 5.12, the grain size was refined to a range of 100–200 nm. Additionally, the aging treatment following severe plastic deformation brought about a significant change in the traditional lamellar precipitation mode of the second phase Mg<sub>17</sub>Al<sub>12</sub> in the magnesium alloy. Instead, spherical precipitation occurred.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142319309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-23DOI: 10.1016/j.rinp.2024.107988
Photonic waveguide structures that use periodic metal grooves and periodically perforated metal slits (PPMSs) can laterally confine Sommerfeld and Zenneck surface waves of metals with the electric field accumulation among metal interspaces in the terahertz (THz) region, instead of the total internal reflection principle of dielectric slab media. For the efficiency enhancements of THz-wave coupling and slab–waveguide confinement, specific integrators with high refractive indices or specified for input angles of transverse magnetic polarized waves, such as prisms, metal blades, and waveguides, are requested to excite spoof surface plasmons in the THz region. However, the integrator-assembled slab–waveguides encounter challenges of THz pulse-wave communication in compact and low-distortion systems. A resonant waveguide grating structure based on PPMSs is experimentally demonstrated to confine THz lateral waves from the plane-wave radiation in free space. The open frame and periodic metal cavities of PPMSs can work as a slab–waveguide to transmit structural confined waveguide modes with forwarding evanescent waves of Fabry–Pérot resonance. For 0.1–1 THz waves, the short wavelengths that are both less than half the metal slit width and 3.75 times the metal thickness can lead to zero dispersion and the highest confinement factor in a slab–waveguide for PPMS-confined THz waves. This behavior is opposite to the high structural dispersion in confined THz waves of surface plasmonic devices.
{"title":"Dispersion-free characterization of terahertz slab–waveguide modal confinement based on a metal Bragg grating structure","authors":"","doi":"10.1016/j.rinp.2024.107988","DOIUrl":"10.1016/j.rinp.2024.107988","url":null,"abstract":"<div><div>Photonic waveguide structures that use periodic metal grooves and periodically perforated metal slits (PPMSs) can laterally confine Sommerfeld and Zenneck surface waves of metals with the electric field accumulation among metal interspaces in the terahertz (THz) region, instead of the total internal reflection principle of dielectric slab media. For the efficiency enhancements of THz-wave coupling and slab–waveguide confinement, specific integrators with high refractive indices or specified for input angles of transverse magnetic polarized waves, such as prisms, metal blades, and waveguides, are requested to excite spoof surface plasmons in the THz region. However, the integrator-assembled slab–waveguides encounter challenges of THz pulse-wave communication in compact and low-distortion systems. A resonant waveguide grating structure based on PPMSs is experimentally demonstrated to confine THz lateral waves from the plane-wave radiation in free space. The open frame and periodic metal cavities of PPMSs can work as a slab–waveguide to transmit structural confined waveguide modes with forwarding evanescent waves of Fabry–Pérot resonance. For 0.1–1 THz waves, the short wavelengths that are both less than half the metal slit width and 3.75 times the metal thickness can lead to zero dispersion and the highest confinement factor in a slab–waveguide for PPMS-confined THz waves. This behavior is opposite to the high structural dispersion in confined THz waves of surface plasmonic devices.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142322174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-23DOI: 10.1016/j.rinp.2024.107983
By the bosonization and renormalization-group schemes, a half-filled Hubbard chain with density-dependent hopping is investigated at weak coupling. The model involved has an electron–hole symmetry and an SO(4) symmetry. The phase diagram consists of three different phases divided by a charge transition at on-site repulsion and a spin transition at , with , including a Mott insulator with the SDW correlation, a dimerized insulator with the BCDW correlation, and a Luttinger metal with the coexisting TS and BSDW correlations. The effective three-body repulsion () and attraction () induce the dimerized and metallic phases, respectively.
{"title":"Phase diagram of the Hubbard chain with symmetric density-dependent hopping","authors":"","doi":"10.1016/j.rinp.2024.107983","DOIUrl":"10.1016/j.rinp.2024.107983","url":null,"abstract":"<div><div>By the bosonization and renormalization-group schemes, a half-filled Hubbard chain with density-dependent hopping is investigated at weak coupling. The model involved has an electron–hole symmetry and an SO(4) symmetry. The phase diagram consists of three different phases divided by a charge transition at on-site repulsion <span><math><mrow><mi>U</mi><mo>=</mo><msub><mrow><mi>U</mi></mrow><mrow><mi>c</mi></mrow></msub></mrow></math></span> and a spin transition at <span><math><mrow><mi>U</mi><mo>=</mo><msub><mrow><mi>U</mi></mrow><mrow><mi>s</mi></mrow></msub></mrow></math></span>, with <span><math><mrow><msub><mrow><mi>U</mi></mrow><mrow><mi>s</mi></mrow></msub><mo>=</mo><mo>−</mo><msub><mrow><mi>U</mi></mrow><mrow><mi>c</mi></mrow></msub><mo>=</mo><mfrac><mrow><mn>16</mn></mrow><mrow><mi>π</mi></mrow></mfrac><mrow><mo>(</mo><msub><mrow><mi>t</mi></mrow><mrow><mi>c</mi></mrow></msub><mo>−</mo><mn>1</mn><mo>)</mo></mrow></mrow></math></span>, including a Mott insulator with the SDW correlation, a dimerized insulator with the BCDW correlation, and a Luttinger metal with the coexisting TS and BSDW correlations. The effective three-body repulsion (<span><math><mrow><msub><mrow><mi>t</mi></mrow><mrow><mi>c</mi></mrow></msub><mo>−</mo><mn>1</mn><mo>></mo><mn>0</mn></mrow></math></span>) and attraction (<span><math><mrow><msub><mrow><mi>t</mi></mrow><mrow><mi>c</mi></mrow></msub><mo>−</mo><mn>1</mn><mo><</mo><mn>0</mn></mrow></math></span>) induce the dimerized and metallic phases, respectively.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142322194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-19DOI: 10.1016/j.rinp.2024.107979
Alkaline metal oxides have received significant attention recently due to their abundance, inherent conductivity, optical absorption, and thermal stability. Here, a straightforward co-precipitation method was employed to obtain both undoped BaO and Mo-doped BaO nanoparticles. Various techniques were used to characterize the synthesized nanoparticles’ structural, Raman spectral, optical, thermal, and electrical properties. X-ray diffraction (XRD) results revealed that Mo was successfully doped into tetragonal nanocrystalline BaO. The W-H plot showed that as Mo doping increases from 2 % to 6 %, the crystallite size grows while the lattice structure remains well-ordered with even strain distribution. Scanning electron microscopy (SEM) was used to examine its surface features. The purity and crystalline character of the samples were further confirmed via Raman spectroscopy, which shows that the peak intensity of the spectra increases with the increase of particle size owing to the rise in the force constant. UV spectroscopy was used to observe the energy band gap, which is found to decrease from 4.2 eV to 3.8 eV, and then it drops to 3.4 eV as the Mo content increases. This is reasonable because of the size-dependent attraction between metallic ions and conduction electrons. PL spectra concluded that Mo doping leads to the enhancement of the optical characteristics of BaO. Adding Mo to BaO also modifies the material’s thermal properties, potentially affecting its suitability for applications that require thermal durability. This finding exhibits that even slight doping of Mo4+ into BaO can significantly impact their structural, thermal, optical, and electrical characteristics. It enriches the existing body of knowledge of BaO nanoparticles and lays the foundation for its future research.
碱性金属氧化物因其丰富的资源、固有的导电性、光吸收性和热稳定性而受到广泛关注。本文采用直接共沉淀法获得了未掺杂的 BaO 和掺杂 Mo 的 BaO 纳米粒子。研究人员采用多种技术对合成的纳米粒子的结构、拉曼光谱、光学、热学和电学特性进行了表征。X 射线衍射 (XRD) 结果表明,钼成功地掺杂到了四方纳米晶 BaO 中。W-H 图显示,随着钼掺杂量从 2% 增加到 6%,晶粒尺寸不断增大,而晶格结构仍然井然有序,应变分布均匀。扫描电子显微镜(SEM)用于检查其表面特征。拉曼光谱进一步证实了样品的纯度和结晶特性。拉曼光谱显示,由于力常数的增加,光谱的峰值强度随着粒度的增加而增加。紫外光谱法用于观察能带间隙,发现随着钼含量的增加,能带间隙从 4.2 eV 下降到 3.8 eV,然后又下降到 3.4 eV。这是合理的,因为金属离子和传导电子之间的吸引力与尺寸有关。聚光光谱得出的结论是,掺杂钼可增强 BaO 的光学特性。在 BaO 中添加钼还会改变材料的热特性,从而可能影响其在需要热耐久性的应用中的适用性。这一发现表明,即使在 BaO 中轻微掺入 Mo4+,也会对其结构、热学、光学和电学特性产生重大影响。它丰富了有关 BaO 纳米粒子的现有知识体系,并为今后的研究奠定了基础。
{"title":"Facile co-precipitation synthesis of nano-molybdenum-doped BaO nanoparticles and their physical characterization","authors":"","doi":"10.1016/j.rinp.2024.107979","DOIUrl":"10.1016/j.rinp.2024.107979","url":null,"abstract":"<div><div>Alkaline metal oxides have received significant attention recently due to their abundance, inherent conductivity, optical absorption, and thermal stability. Here, a straightforward co-precipitation method was employed to obtain both undoped BaO and Mo-doped BaO nanoparticles. Various techniques were used to characterize the synthesized nanoparticles’ structural, Raman spectral, optical, thermal, and electrical properties. X-ray diffraction (XRD) results revealed that Mo was successfully doped into tetragonal nanocrystalline BaO. The W-H plot showed that as Mo doping increases from 2 % to 6 %, the crystallite size grows while the lattice structure remains well-ordered with even strain distribution. Scanning electron microscopy (SEM) was used to examine its surface features. The purity and crystalline character of the samples were further confirmed via Raman spectroscopy, which shows that the peak intensity of the spectra increases with the increase of particle size owing to the rise in the force constant. UV spectroscopy was used to observe the energy band gap, which is found to decrease from 4.2 eV to 3.8 eV, and then it drops to 3.4 eV as the Mo content increases. This is reasonable because of the size-dependent attraction between metallic ions and conduction electrons. PL spectra concluded that Mo doping leads to the enhancement of the optical characteristics of BaO. Adding Mo to BaO also modifies the material’s thermal properties, potentially affecting its suitability for applications that require thermal durability. This finding exhibits that even slight doping of Mo<sup>4+</sup> into BaO can significantly impact their structural, thermal, optical, and electrical characteristics. It enriches the existing body of knowledge of BaO nanoparticles and lays the foundation for its future research.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2211379724006648/pdfft?md5=fba97975a17813173ad5e853ffc16a99&pid=1-s2.0-S2211379724006648-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142310780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-19DOI: 10.1016/j.rinp.2024.107964
Near-infrared photodetectors were fabricated by incorporating formamidinium lead iodide (FAPbI3) quantum dots (QDs) as the light-harvesting layer. Through systematic optimization of the device architecture, high device performance was achieved by utilizing PCBM as the electron transport material and a 50 nm-thick TAPC film as the hole transport layer. The energy level alignment between PCBM and the FAPbI3 QDs enabled efficient exciton dissociation and hole blocking, while the optimized TAPC thickness decrease current leakage pathways. The resulting photodetectors exhibited an impressive external quantum efficiency of 59.56 % at 750 nm, along with a high specific detectivity of 2.63 x 1011 Jones. A broadband photoresponse from 300–900 nm was observed, as well as a fast temporal response with 30.58/31.26 μs rise/fall times. A substantial linear dynamic range of 61.5 dB was achieved under 780 nm illumination. Furthermore, the low dark current densities facilitated by the judiciously selected materials and thicknesses contributed to the excellent overall device performance. The device performance of the PCBM/FAPbI3 QDs/TAPC system demonstrate its promising potential for near-infrared optoelectronic applications requiring high sensitivity, speed, and broad spectral response, opening up opportunities for further advances in photodetection as well as other relevant device technologies.
{"title":"Ultra-broadband Photodetectors Based on Formamidinium Lead Iodide Quantum Dots","authors":"","doi":"10.1016/j.rinp.2024.107964","DOIUrl":"10.1016/j.rinp.2024.107964","url":null,"abstract":"<div><p>Near-infrared photodetectors were fabricated by incorporating formamidinium lead iodide (FAPbI<sub>3</sub>) quantum dots (QDs) as the light-harvesting layer. Through systematic optimization of the device architecture, high device performance was achieved by utilizing PCBM as the electron transport material and a 50 nm-thick TAPC film as the hole transport layer. The energy level alignment between PCBM and the FAPbI<sub>3</sub> QDs enabled efficient exciton dissociation and hole blocking, while the optimized TAPC thickness decrease current leakage pathways. The resulting photodetectors exhibited an impressive external quantum efficiency of 59.56 % at 750 nm, along with a high specific detectivity of 2.63 x 10<sup>11</sup> Jones. A broadband photoresponse from 300–900 nm was observed, as well as a fast temporal response with 30.58/31.26 μs rise/fall times. A substantial linear dynamic range of 61.5 dB was achieved under 780 nm illumination. Furthermore, the low dark current densities facilitated by the judiciously selected materials and thicknesses contributed to the excellent overall device performance. The device performance of the PCBM/FAPbI<sub>3</sub> QDs/TAPC system demonstrate its promising potential for near-infrared optoelectronic applications requiring high sensitivity, speed, and broad spectral response, opening up opportunities for further advances in photodetection as well as other relevant device technologies.</p></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2211379724006491/pdfft?md5=c73b543248622803cbe75c638abd4695&pid=1-s2.0-S2211379724006491-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142271452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}