Results in Physics最新文献

{"title":"Novel direct and wide bandgap SiC semiconductors: High-throughput screening and density functional theory","authors":"Heng Liu ,&nbsp;Mengjiang Xing ,&nbsp;Qingyang Fan","doi":"10.1016/j.rinp.2024.107966","DOIUrl":"10.1016/j.rinp.2024.107966","url":null,"abstract":"<div><p>High-throughput computing has been widely used in the field of material design because of its feasibility, efficiency, accuracy and predictability. Fourteen new high-temperature SiC polymorphs were theoretically established via high-throughput screening, and density functional theory (DFT) was employed to investigate their physical properties. The new SiC polymorphs have mechanical and thermodynamic stability, and 10 of them can even maintain thermal stability at high temperatures up to 2000 K. The electronic band structure obtained by the Heyd–Scuseria–Ernzerhof (HSE06) hybrid functional shows that 13 of the new SiC polymorphs have a wide bandgap, 6 of which have a direct or quasi-direct bandgap. Notably, compared with those of 3C-SiC, the holes of <em>I</em>4₁/<em>a</em>-II SiC, <em>I</em>4₁/<em>a</em>-IV SiC, and <em>P</em>4/<em>ncc</em>-I SiC have lower effective masses in the [1<!--> <!-->0<!--> <!-->0] direction; in particular, the hole effective mass of <em>P</em>4/<em>ncc</em>-I SiC is only approximately 4.6 % of that of 3C-SiC. Owing to their direct wide bandgap, excellent thermal stability and low effective mass, the newly proposed SiC polymorphs have great application potential in the field of microelectronics.</p></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"65 ","pages":"Article 107966"},"PeriodicalIF":4.4,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S221137972400651X/pdfft?md5=de2187002d01bfef40ad9799973fddb9&pid=1-s2.0-S221137972400651X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142243035","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}

{"title":"Accurate high-temperature profile sensing with dense multipoint arrays of regenerated fiber Bragg gratings","authors":"Andrea Stadler ,&nbsp;Andreas Zeisberger ,&nbsp;Fabian Buchfellner ,&nbsp;Alexander Roehrl ,&nbsp;Alexander W. Koch ,&nbsp;Johannes Roths","doi":"10.1016/j.rinp.2024.107970","DOIUrl":"10.1016/j.rinp.2024.107970","url":null,"abstract":"<div><div>A spectrally and spatially dense sensor array consisting of 15 regenerated fiber Bragg gratings (RFBGs) over a length of 30 mm is presented for precise and fast multipoint temperature sensing up to 700°C. For the first time, it could be shown that with a dense fiber Bragg grating (FBG)-based sensor array the accuracy requirements of Class 1 thermocouples could be achieved and even exceeded. This also represents the highest spatial density of FBG-based high-temperature multipoint sensing reported so far. The mitigation of broadband losses during the regeneration process was studied, revealing the advantages of the low broadband loss characteristics of the RFBGs, especially when larger numbers of measuring points are required. Low measurement uncertainties were achieved by a new, improved calibration methodology and by an analysis of interferences of an FBG with the side lobes of spectrally neighboring FBGs as well as their suppression by a suitable arrangement of the Bragg wavelengths within the array and corresponding data processing. The capabilities of this multipoint sensor technique were demonstrated by resolving the temperature profile within the calibration volume of a calibration furnace and by resolving the temporal and spatial temperature gradients within the flame of a Bunsen burner. The results are of great importance for fiber-optic sensing of high-temperature profiles in real-world applications.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"65 ","pages":"Article 107970"},"PeriodicalIF":4.4,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2211379724006557/pdfft?md5=ba7be6ac652283ef4454821e6f18f9ba&pid=1-s2.0-S2211379724006557-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142315976","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}

{"title":"On-chip photoelectric hybrid convolutional accelerator based on Bragg grating array","authors":"Kaiteng Cai ,&nbsp;Liqi Chen ,&nbsp;Yunming Zhang ,&nbsp;Juncheng Wang ,&nbsp;Wei Lin ,&nbsp;Shaoxiang Duan ,&nbsp;Bo Liu","doi":"10.1016/j.rinp.2024.107968","DOIUrl":"10.1016/j.rinp.2024.107968","url":null,"abstract":"<div><p>We propose an on-chip photoelectric hybrid convolution accelerator based on Bragg grating array. The weight of the convolution kernel can be adjusted by controlling the central wavelengths of the Bragg grating array. We conducted simulation verification of the functionality and scalability of this on-chip photoelectric hybrid convolution accelerator. Subsequently, we constructed a neural network model to conduct handwritten digit classification simulations using this accelerator, achieving a simulation accuracy of 93.99%. Finally, the concept of the proposed on-chip photoelectric hybrid convolution accelerator is successfully verified. Due to the merits of Bragg grating, the proposed scheme paves the way for realizing high-performance on-chip optical neural networks.</p></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"65 ","pages":"Article 107968"},"PeriodicalIF":4.4,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2211379724006533/pdfft?md5=70f14562bf1c598b02309664917807d0&pid=1-s2.0-S2211379724006533-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142233707","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}

{"title":"Graphene-based metamaterial ultrawideband absorber with enhanced terahertz performance","authors":"Abbas Movahednia ,&nbsp;V. Mashayekhi ,&nbsp;Ehsan Zareian-Jahromi ,&nbsp;Seyed Mohamad Hashemi","doi":"10.1016/j.rinp.2024.107965","DOIUrl":"10.1016/j.rinp.2024.107965","url":null,"abstract":"<div><p>In this paper, we present a graphene-based metamaterial ultrawideband absorber operating in the terahertz regime. The absorber is composed of two patterned and continuous graphene layers, a bottom gold layer, and a SiO₂ substrate that separates the continuous graphene layer from the gold layer. The absorption spectrum is enhanced by integrating a graphene resonator with water, which has frequency-dependent permittivity. The water is encapsulated in polytetrafluoroethylene (PTFE) in the form of a circular ring sandwiched between the two graphene layers. Simulation results show that the absorber attains a 90 % absorption bandwidth of about 14.55 THz. The proposed absorber is polarization-insensitive under normal incidence. For TE polarization, the absorption level remains stable for incident angles <em>θ</em> from 0° to 55° across the entire frequency band (14.55 THz), except for the 5–8 THz range. For TM polarization, the absorption level remains stable for <em>θ</em> ranging from 0° to 60° over the entire bandwidth. Additionally, the absorption level is consistent for both TM and TE polarizations across the entire bandwidth for incident angles <em>φ</em> from 0° to 90°.</p></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"65 ","pages":"Article 107965"},"PeriodicalIF":4.4,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2211379724006508/pdfft?md5=b8819cc63736b46f73af5e5beff53958&pid=1-s2.0-S2211379724006508-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142271451","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}

{"title":"Kink effect on the lattice properties of one-dimensional carbyne nanocrystals under high temperature","authors":"Yan He ,&nbsp;Ziqing Huang ,&nbsp;Huakai Xu ,&nbsp;Xingyuan Chen ,&nbsp;Gang Ouyang","doi":"10.1016/j.rinp.2024.107957","DOIUrl":"10.1016/j.rinp.2024.107957","url":null,"abstract":"<div><p>Carbyne nanocrystal (CN), as a kind of one-dimensional (1D) <em>sp</em>-hybridized carbon allotrope, has attracted much attention due to its excellent optical and transport properties. However, the lattice properties of 1D CNs under high temperature remain unclear. In our work, we investigate the stability and lattice properties of 1DCNs based on the atomic-bond-relaxation (ABR) approach and first-principles calculations. We find the change of transverse vibration frequencies and bond kinks induced by the thermal effect plays a significant role in the mechanical properties of 1D CNs. We establish a relationship between kink angle and phonon vibration modes, giving a deep inside into high frequency and low-frequency vibration behavior of 1D CNs. Our results indicate the phonon vibration modes modulated by kinks under applied temperatures can lead to a negative thermal expansion behavior in the axial direction of 1D CNs, suggesting an effective way to control the thermal properties of 1D CNs for practical applications.</p></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"65 ","pages":"Article 107957"},"PeriodicalIF":4.4,"publicationDate":"2024-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2211379724006429/pdfft?md5=f56c5a64bef3cc4e01c5ca17ecd662d0&pid=1-s2.0-S2211379724006429-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142163548","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}

{"title":"Nonreciprocal conversion based on line trajectory near exceptional points","authors":"Qingjie Liu ,&nbsp;Wenrui Liu ,&nbsp;Tong Li ,&nbsp;Yingquan Ao ,&nbsp;Shaolin Ke","doi":"10.1016/j.rinp.2024.107959","DOIUrl":"10.1016/j.rinp.2024.107959","url":null,"abstract":"<div><p>Spatio-temporal permittivity modulation can simultaneously impart wave vector and frequency shifts during an indirect photonic transition process where nonreciprocal responses are accomplished. Here, we combine the nonreciprocity with exceptional points (EPs) by employing line parameter trajectory to a spatio-temporally modulated waveguide. The instantaneous state evolutions on direction-dependent Riemann sheets are thus different in forward and backward directions. Light propagates through the structure is nonreciprocal. Forwardly, an arbitrary incident wave will convert to a combination of the two waveguide modes with same intensity. Backwardly, the waves almost entirely convert to one specific mode. The conversion efficiency is more than 80% and robust to the line design. The operating wavelength is in the telecommunications band, conducive to integration with other chips. Compared to the widely used loop path, the line path has the merit of easy preparation in experiments as only one parameter is changed. The research sheds light on the optical devices such as isolator and amplifier.</p></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"65 ","pages":"Article 107959"},"PeriodicalIF":4.4,"publicationDate":"2024-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2211379724006442/pdfft?md5=89eca6bc7178024140e185698d6540d7&pid=1-s2.0-S2211379724006442-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142243037","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}

{"title":"Design and optimization of broadband near-perfect absorber based on transition metal nitrides thin-films for solar energy harvesting","authors":"Chanphen Prikaen,&nbsp;Papichaya Chaisakul,&nbsp;Surasak Chiangga","doi":"10.1016/j.rinp.2024.107950","DOIUrl":"10.1016/j.rinp.2024.107950","url":null,"abstract":"<div><p>Broadband metamaterial absorbers hold promise for solar energy harvesting, but their complex designs and use of expensive noble metals hinder scalability and thermal stability. Additionally, traditional design methods are time-consuming. We propose a novel approach that combines a genetic algorithm with the transfer matrix method to optimize both material composition and layer structure for large-scale, cost-effective, and thermally stable solar absorbers. This method enables the design of near-perfect absorbers with an average absorptance exceeding 90 % and over 80 % across a broad wavelength range (0.3–2.5 μm) within the key solar spectrum. By optimizing the arrangement of metal and insulator layers using nitride materials (e.g., vanadium nitride), we achieve superior performance compared to traditional metal–insulator and insulator–metal structures. This optimization utilizes resonant absorption and the inherent absorption of metal layers. Our work paves the way for efficient and scalable solar energy harvesting devices.</p></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"65 ","pages":"Article 107950"},"PeriodicalIF":4.4,"publicationDate":"2024-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2211379724006351/pdfft?md5=0f0f644cc6f937291deb7520fb208f01&pid=1-s2.0-S2211379724006351-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142163549","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}

{"title":"Shot-noise-limited optical polarimetry with spin-alignment and magnetism decoupling","authors":"Xing Heng ,&nbsp;Xiaofei Huang ,&nbsp;Weiyi Wang ,&nbsp;Fan Wang ,&nbsp;Dinghui Gong ,&nbsp;Chang Liu ,&nbsp;Guoqing Tian ,&nbsp;Jie Zheng ,&nbsp;Yueyang Zhai ,&nbsp;Kai Wei","doi":"10.1016/j.rinp.2024.107960","DOIUrl":"10.1016/j.rinp.2024.107960","url":null,"abstract":"<div><p>Quantum non-demolition measurement with an off-resonance polarized probe is a widely utilized technique for atomic sensors. We observe previously unexplored spin-alignment polarization induced by the far-detuned off-resonance linear probe in an ultrasensitive optical polarimetry. The evolution of probe-generated multipole moments exacerbates probe noise due to strong magnetic couplings. We demonstrate a method to decouple spin-alignment from magnetic fields by manipulating the multipole moments in zero-fields. The probe noise is suppressed by 10 dB with the proposed method, achieving a noise floor at the standard quantum limit. The realized shot-noise-limited optical polarimetry holds significant promise for atomic sensors aimed at ultra-sensitivity.</p></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"65 ","pages":"Article 107960"},"PeriodicalIF":4.4,"publicationDate":"2024-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2211379724006454/pdfft?md5=50e3aa6bc8be5d4351bcbc40dd2178c4&pid=1-s2.0-S2211379724006454-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142172680","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}

{"title":"WITHDRAWN: Differential Lucy-Richardson-Rosen algorithm for near diffraction-limited image restoration assisting by a wavefront sensor","authors":"Lianhui Zheng, Xiaoyan Wang, Wan Li, Xiaofu Xu, Zhongjian Gao, Hailian Hong, Huixian Yan, Siyu Huang, Naiting Gu","doi":"10.1016/j.rinp.2024.107951","DOIUrl":"https://doi.org/10.1016/j.rinp.2024.107951","url":null,"abstract":"","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"57 1","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142269909","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"A numerical study on MHD Casson fluid flow in a non-uniform rough channel with temperature-dependent properties using OHAM","authors":"Hanumesh Vaidya ,&nbsp;K.V. Prasad ,&nbsp;Rajashekhar Choudhari ,&nbsp;Jyoti Shetty ,&nbsp;Shivaleela","doi":"10.1016/j.rinp.2024.107939","DOIUrl":"10.1016/j.rinp.2024.107939","url":null,"abstract":"<div><p>This study explores the complex dynamics of magnetohydrodynamic (MHD) Casson fluid in a non-uniform rough channel, focusing on the effects of temperature-dependent viscosity and variable thermal conductivity under no-slip boundary conditions. The study employs an innovative approach by utilising a rough surface with irregular textures to analyse flow patterns and assess drag forces on channel objects. A novel mathematical model, governed by continuity, momentum, and heat transfer equations, is developed and transformed into dimensionless, nonlinear Ordinary Differential Equations (ODEs) using non-dimensional quantities and fundamental assumptions. The Optimal Homotopy Analysis Method (OHAM) is applied to solve these equations to enhance convergence speed and accuracy. The research explores the impact of surface roughness on velocity profiles and temperature distributions under various physical constraints. Numerical simulations are conducted to determine skin friction coefficients and Nusselt numbers. Furthermore, the study examines the influence of confined boluses on fluid flow in diverse physiological conditions. A comprehensive analysis is performed to elucidate the combined effects of surface roughness on fluid passage, including flow separation, pattern alterations, pressure distribution and drop, heat transfer characteristics, and flow resistance. The intricate interplay between temperature-dependent viscosity, varying thermal conductivity, and surface roughness is thoroughly investigated to explain the complex dynamics of MHD Casson fluid movement in non-uniform channels. Implementing a magnetic field over the rough, non-uniform channel is found to provide stability and prevent fluid overflow. This research has significant real-world applications, including soil erosion prevention, blood flow regulation in arteries, and optimisation of hydropower channels and penstocks. By enhancing our understanding of flow dynamics through rough and non-uniform channels, this study contributes valuable insights into both theoretical fluid mechanics and practical engineering applications.</p></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"64 ","pages":"Article 107939"},"PeriodicalIF":4.4,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2211379724006247/pdfft?md5=1a12641ea8615084e5c509791a8a0849&pid=1-s2.0-S2211379724006247-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142148300","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}