Optik最新文献

{"title":"Broadband linear to circular polarization conversion over extreme angle of view using a single layer Frequency Selective Surface","authors":"M. Askari ,&nbsp;M. Heydari ,&nbsp;E. Zarezadeh","doi":"10.1016/j.ijleo.2024.172201","DOIUrl":"10.1016/j.ijleo.2024.172201","url":null,"abstract":"<div><div>A single-layer Frequency-Selective Surface (FSS) is presented that splits the incident power equally in transmission and reflection. The FSS converts the linear polarization of the incident wave to circular polarization. The handedness of transmitted and reflected circularly polarized waves are orthogonal and it can be reversed by changing the linear polarization of the incident wave. The FSS is a single-layer patterned surface consists of rectangular patches that are connected by narrow strips from one side. The performance of the structure is evaluated using full-wave simulation. The proposed FSS exhibits a wide-band frequency response with a robust angular performance for up to 80° illumination angles. The transmittance/reflectance is <span><math><mrow><mo>−</mo><mn>3</mn><mo>±</mo><mn>0.15</mn></mrow></math></span> dB, the axial ratio is smaller than <span><math><mn>0.8</mn></math></span> dB and the phase difference is <span><math><mrow><msup><mrow><mn>90</mn></mrow><mrow><mi>o</mi></mrow></msup><mo>±</mo><msup><mrow><mn>10</mn></mrow><mrow><mi>o</mi></mrow></msup></mrow></math></span> for both right-handed and left-handed circularly polarized scattered waves over all incident angles. Full-wave simulation of the structure demonstrates that the 3 dB axial ratio bandwidth is 85 %, 102 %, and 95 % for the reflected left-handed circularly polarized wave and 85 %, 104 %, and 125 % for the transmitted left-handed circularly polarized wave under TM and TE excitation by the incident angles <span><math><mrow><msup><mrow><mn>0</mn></mrow><mrow><mi>o</mi></mrow></msup><mo>,</mo><mspace></mspace><msup><mrow><mn>45</mn></mrow><mrow><mi>o</mi></mrow></msup><mo>,</mo><mspace></mspace><msup><mrow><mi>and</mi><mn>80</mn></mrow><mrow><mi>o</mi></mrow></msup></mrow></math></span>, respectively. The bandwidth and angular performance is enhanced compared to polarization converters demonstrated in recent literature. The proposed design presents a simple and low-cost solution to generate orthogonal handedness of circular polarization in both reflection and transmission with a wide bandwidth and a broad angular stability.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"327 ","pages":"Article 172201"},"PeriodicalIF":3.1,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143620468","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":"Design and analysis of an optical demultiplexer based on Bragg grating using plasmonic waveguides and defects","authors":"Razieh SoltaniSarvestani,&nbsp;Rahim Ghayour,&nbsp;Maryam Mohitpour","doi":"10.1016/j.ijleo.2024.172209","DOIUrl":"10.1016/j.ijleo.2024.172209","url":null,"abstract":"<div><div>An infrared multi-channel optical de/multiplexer consisting of plasmonic waveguides is designed and numerically investigated. The proposed device applies the advantages of surface plasmon polaritons and the Bragg filter waveguides to realize the multi/demulti-plexing function. In this work, the application of single tuned defect in the middle of Bragg grating and a tuned nano-cavity for each channel in the proposed structures present some novel results as demultiplexers operation. According to the simulation results, the transmittances of the output channels reach up to 50 % at the desired wavelengths. Thereafter, the geometries of the proposed structures have been optimized to enhance the functional characteristics. Within the channels, a wavelength spacing of 130 nm and a crosstalk around − 22.6 dB is obtained for the optimized four-channel structure in the desired operating wavelength range. In addition to presenting an innovative structure in this article, the performance parameters such as crosstalk and transmittance are at higher levels compared to those of the devices presented in similar works. The simple fabrication process, high efficiency, narrow passband and wide operating range make the proposed micro device a suitable choice for several applications in optical telecommunications.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"322 ","pages":"Article 172209"},"PeriodicalIF":3.1,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143162216","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":"Research on lead ion sensing based on micro-nano fiber coupler cascade tilted fiber grating","authors":"Yue Feng ,&nbsp;Haodong Wu ,&nbsp;Mohammed Hazaea Esmail ,&nbsp;Chi Liu ,&nbsp;Xin Liu ,&nbsp;Chao Wang ,&nbsp;Tao Shen","doi":"10.1016/j.ijleo.2024.172200","DOIUrl":"10.1016/j.ijleo.2024.172200","url":null,"abstract":"<div><div>As water pollution becomes increasingly severe, human health is facing threats from heavy metal lead ions in water. Therefore, detecting trace amounts of Pb²⁺ in water has become crucial. Fiber optic sensors have garnered significant attention in the sensor research field due to their small size, high sensitivity, and ease of integration. However, developing a fiber optic sensor capable of detecting Pb²⁺ at the pmol/L level poses a challenge. The study proposes a novel micro-nano fiber coupler cascaded tilted fiber grating (MFC-TFG) sensor, which is modified with glutathione complexed titanium carbide MXene (GSH@Ti₂C) for the detection of Pb²⁺ concentrations in water environments. It exhibits a selective response to Pb²⁺ and achieves a limit of detection (LOD) of 0.624 pM (0.013 ng/dL). In the sensor structure, the cladding modes of the TFG can respond to changes in refractive index (RI) and temperature, while the core mode is only affected by temperature. Consequently, the MFC-TFG sensor can simultaneously detect environmental parameters of RI and temperature. By combining fiber optic designs and optimizing sensitive materials, the study addresses ultra-low Pb²⁺ detection, offering a robust fiber optic solution for heavy metal sensing.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"322 ","pages":"Article 172200"},"PeriodicalIF":3.1,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143162212","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":"Polarization-independent ultra-sensitive graphene sensor for the detection of prostate-specific antigen","authors":"Yousef Rafighirani,&nbsp;Javad Javidan,&nbsp;Hamid Heidarzadeh","doi":"10.1016/j.ijleo.2024.172196","DOIUrl":"10.1016/j.ijleo.2024.172196","url":null,"abstract":"<div><div>This study presents a three-band absorbent structure based on cut graphene, which has been used as a biosensor for the detection of prostate-specific antigen (PSA) due to the tunability of the resonance frequency of graphene and the polarization-independent capability of the proposed structure. The sensor is composed of three layers: a copper substrate with a conductivity of 5.831 ×<span><math><msup><mrow><mn>10</mn></mrow><mrow><mn>7</mn></mrow></msup></math></span>, a silicon dioxide (SiO₂) dielectric layer with a permittivity of 3.9, and a graphene layer with strategic cuts to enhance absorption. The performance of the proposed structure was evaluated by measuring its absorption at three terahertz frequency bands: 3.9 THz, 8.52 THz, and 11.83 THz, achieving absorption values of 99.65 %, 99.25 %, and 99.78 %, respectively. These high absorption rates make the sensor an excellent candidate for biosensing applications, particularly for detecting PSA in clinical samples. By testing the sensor with analytes containing PSA at 100, 200, 300, and 400 PM concentrations, the refractive index values were 1.3477, 1.3654, 1.3831, and 1.4008, respectively. When the analyte layer is placed on the three-band absorber structure, the peak shift is absorbed, enabling the detection of the desired analyte. The proposed structure demonstrated remarkable sensitivity, achieving 2638.4 GHz/RIU at a refractive index of 1.3831 and a frequency of 11.451 THz. This high sensitivity is particularly advantageous for detecting low concentrations of analytes. Such a sensor has great potential for enhancing the detection of biomarkers. These findings highlight the sensor's potential for high-sensitivity PSA detection, offering a valuable tool for early prostate cancer diagnosis and screening.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"322 ","pages":"Article 172196"},"PeriodicalIF":3.1,"publicationDate":"2024-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143162213","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":"Full-Stokes polarization short-wave infrared photodetector based on the doubly regulated dielectric metasurfaces","authors":"Bo Cheng ,&nbsp;Yuxiao Zou ,&nbsp;Guofeng Song","doi":"10.1016/j.ijleo.2024.172198","DOIUrl":"10.1016/j.ijleo.2024.172198","url":null,"abstract":"<div><div>Fully polarization photodetectors based on miniature metasurface filters have attracted much attention because they can directly detect polarized signals that cannot be perceived by the human eye. Although some structures have been proposed to break the spatial symmetry to obtain chirality, the circular polarization extinction ratio of the polarization detector is still not high enough, which severely limits the application of the device in complex polarization scenarios. Here, we gradually enhance the structural chirality of the metasurface based on the dual manipulation of displacement and rotation, and the circular dichroism and circular polarization extinction ratio of the circularly polarized photodetector reach 86 % and 22 dB, respectively, at an operating wavelength of 1530 nm. Four linearly polarized pixels and two chiral pixels can accurately restore the Stokes parameter of the polarized light through the 6-in-1 scheme, and their errors of the degree of linear polarization and the degree of circular polarization are −25 dB and −20 dB, respectively. This fully polarized photodetector is expected to advance the detection dimension from the traditional intensity detection to the new polarization detection field.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"322 ","pages":"Article 172198"},"PeriodicalIF":3.1,"publicationDate":"2024-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143162211","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":"Broadband reflectarray antenna using circular ring additional helical microstrip lines","authors":"Yunqi Zhang ,&nbsp;Hao Guo ,&nbsp;Bin Huang ,&nbsp;Xuanming Zhang ,&nbsp;Jiajia Cui ,&nbsp;Jianxiao Wang ,&nbsp;Shanzhe Wang","doi":"10.1016/j.ijleo.2024.172197","DOIUrl":"10.1016/j.ijleo.2024.172197","url":null,"abstract":"<div><div>This article proposes a new type of single-layer unit aimed at improving the operating bandwidth of reflectarray antennas (RA). Specially, the novel element comprised of a circular ring patch combined to four helical microstrip lines (HMLs), where the rotation angle of each HML around the center of the circular ring differs by 90°. The optimized unit can achieve a linear phase response of 400° phase at 10 GHz. Additionally, the phase response curves remain nearly parallel over the 8–13 GHz band, so that using the unit as a broadband reflector antenna in the X-band is an effective means. Finally, an octagonal aperture center fed reflectarray antenna consisting of 464 elements was designed and tested. The test results indicate that the designed RA achieves a 1-dB gain bandwidth of 35.5 % from 8.8 to 12.6 GHz. In addition, the sidelobe level for the E-plane is tested to be below −19 dB at 10 GHz.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"322 ","pages":"Article 172197"},"PeriodicalIF":3.1,"publicationDate":"2024-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143162210","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":"Electric field-induced switching of bands in graphene-assisted metamaterial absorber","authors":"Amrendra Kumar ,&nbsp;Raghwendra Kumar","doi":"10.1016/j.ijleo.2024.172190","DOIUrl":"10.1016/j.ijleo.2024.172190","url":null,"abstract":"<div><div>A dual-band metamaterial absorber based on graphene is designed and numerically analyzed for operation at near-infrared frequencies. The structure comprises a one-dimensional silicon grating placed on a single layer graphene, supported by a gold substrate. The working mechanisms of the absorber are understood with the help of numerical simulations, which are performed using Computer Simulation Technology (CST) Microwave Studio. The simulation results indicate that the critical coupling enabled through the guided-mode resonance in the system significantly enhances the dual-band absorption. The absorber demonstrates two narrow absorption bands with corresponding absorptances of about 1 and 0.97 at wavelengths of 665.58 nm and 1134 nm, respectively. The number of absorption bands in this design can be electrically adjusted by leveraging the tunable conductivity of graphene. The absorber can be used as a dual-band absorber/single-band absorber or alike a perfect reflector. The aspects of different geometrical parameters like periodicity, width of the grating ridge, height/depth of the grating ridge and chemical potential of graphene are investigated in detail. Given its dual resonance wavelengths, high absorptance, and tunable band-switching capability, this absorber shows great potential for various applications at near-infrared frequencies.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"322 ","pages":"Article 172190"},"PeriodicalIF":3.1,"publicationDate":"2024-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143162205","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":"Exploring the formation of plasmonic silver nanoparticles and wide range optical energy bandgaps in ion conducting EG–SiO2/AgNO3 hybrid nanofluids for broader functionalities","authors":"R.J. Sengwa,&nbsp;Mukul Saraswat","doi":"10.1016/j.ijleo.2024.172195","DOIUrl":"10.1016/j.ijleo.2024.172195","url":null,"abstract":"<div><div>Multifunctional nanofluids are cutting edge materials of high interest in emerging soft device technologies. In this research, silver ion conducting hybrid nanofluids (NFs) comprising ethylene glycol (EG) base fluid, silicon dioxide (SiO₂) nanoparticles, and silver nitrate (AgNO₃) salt with 0.2–2.0 wt% concentrations, are prepared through a state-of-the-art two-step method and characterized for exploration of their broader functionalities. Ultraviolet-visible (UV-Vis) absorbance spectra of these EG–SiO₂/AgNO₃ NFs exhibited three characteristic bands. The surface plasmon resonance band with maximum intensity at 425 nm signifies the formation of plasmonic silver nanoparticles (AgNPs) through the polyol ions reduction process which transformed these materials to SiO₂-AgNPs nanosuspended hybrid NFs. A relatively intense band at 300 nm evidenced coordinative interactions of silver ions with EG molecules. A strong absorption band having onset at about 265 nm is attributed to electronic transitions from the EG molecules. Distinct energy bandgaps, ranges 4.77–4.55, 3.75–3.60, and 2.22–1.96 eV marginally altered with salt concentrations, categorized these soft plasmonic materials of wide bandgap semiconductors. Optical characterization revealed the applicability of these hybrid NFs in photo-sensing, UV shielding, and the design of bandgap tunable optoelectronics. High static dielectric permittivity range 40.30–41.44 and ionic conductivity orders 10^–3–10^–4 S/cm, at 298.15 K, characterizes these materials as polar liquid electrolytes which could be used as energy storage, antibacterial agent, and in developing ion sensitive next technology biomedical devices. Newtonian flow behaviour with high dynamic viscosity additionally explains the utilization of these NFs in heat management and high-performance mass transfer systems.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"322 ","pages":"Article 172195"},"PeriodicalIF":3.1,"publicationDate":"2024-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143162208","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":"HfO2-Blue Phosphorus/molybdenum disulfide hybrid structure-based surface plasmon optical refractometric sensor with multiple light source for rapid novel coronavirus detection","authors":"Wahiduzzaman Emon ,&nbsp;Ahmed Afif Rafsan ,&nbsp;Md. Faysal Nayan ,&nbsp;Russel Reza Mahmud ,&nbsp;Nguyen Hoang Hai ,&nbsp;Md. Anwar Hossain","doi":"10.1016/j.ijleo.2024.172191","DOIUrl":"10.1016/j.ijleo.2024.172191","url":null,"abstract":"<div><div>This paper presents a novel hybrid multilayered surface plasmon resonance (SPR) biosensor composed of CaF<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>/TiO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>/Ag/HfO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>/BP-MoS<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> for rapid and precise detection of the novel coronavirus (COVID-19). Utilizing the angular probe attenuation total reflection (ATR) technique, the sensor detects changes in the refractive index (RI) and surface plasmon polaritons (SPPs) resulting from interactions between varying ligand-analyte concentrations. Functionalized with monoclonal antibodies (mAbs) as probe ligands and the virus spike receptor-binding domain (RBD) as the analyte, the sensor enables specific binding that increases concentration in the sensing region, leading to a shift in RI and the SPR angle, thereby affecting the reflectance level. The performance of the sensor was evaluated using numerical analysis techniques such as the finite element method (FEM) and the transfer matrix method (TMM), demonstrating high sensitivity with an angular shift of 412.7972 degrees per refractive index unit (RIU), detection accuracy of 0.3916 degrees per degree, and a figure of merit (FOM) of 161.6627 RIU⁻¹. The multilayered sensor swiftly detects the COVID-19 virus with exceptional angular sensitivity and has been validated for use with a range of biological components within the RI range of 1.20 to 1.35. The study also discusses compatibility with various light sources and potential production techniques with fabrication tolerance, making it broadly applicable for virus detection and advanced biosensing technologies.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"322 ","pages":"Article 172191"},"PeriodicalIF":3.1,"publicationDate":"2024-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143162209","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":"Modelling and optimization of TiO2based two- dimensional photonic crystal for salinity detection in water","authors":"Priyanka Yadav,&nbsp;Ravindra Singh,&nbsp;Ram narayan,&nbsp;Surendra Prasad","doi":"10.1016/j.ijleo.2024.172193","DOIUrl":"10.1016/j.ijleo.2024.172193","url":null,"abstract":"<div><div>In this article, we have presented a computational analysis of two-dimensional photonic crystals (2D- PCs) having circular and elliptical waveguide structures inside a<span><math><mrow><mspace></mspace><msub><mrow><mi>TiO</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow></math></span> host material for the salinity detection in the water. The band structure of the proposed 2D- PCs has been optimized for better salinity detection based on the number of circular and elliptical waveguiding pores taken in the PCs structure and changes in the radius of circular pores and for different major-minor axis of elliptical pores. The electric field profiles corresponding to these structures have also been plotted. The salinity detection sensitivity is calculated by computing the change in transmittance <span><math><mrow><mo>(</mo><msub><mrow><mo>∆</mo><mi>T</mi></mrow><mrow><msub><mrow><mi>n</mi></mrow><mrow><mn>1.333</mn></mrow></msub><mo>−</mo><msub><mrow><mi>n</mi></mrow><mrow><mn>1.35</mn></mrow></msub></mrow></msub></mrow></math></span>) corresponding to changes in refractive indices due to salinity in water. It is observed that maximum sensitivity is obtained corresponding to refractive indices, <span><math><mrow><msub><mrow><mi>n</mi></mrow><mrow><mn>1.333</mn></mrow></msub><mo>,</mo><mspace></mspace><msub><mrow><mi>n</mi></mrow><mrow><mn>1.35</mn></mrow></msub></mrow></math></span> which is equal to 0.9198 in the circular pore in the 2D-PCs structure. For the elliptical pore, the sensitivity is 0.8679.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"322 ","pages":"Article 172193"},"PeriodicalIF":3.1,"publicationDate":"2024-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143162207","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}