Results in Optics最新文献

{"title":"Intense violet electroluminescence of thin SiO2 layers with SnO2 nanocrystals","authors":"Ivan Romanov ,&nbsp;Irina Parkhomenko ,&nbsp;Liudmila Vlasukova ,&nbsp;Elke Wendler ,&nbsp;Fadei Komarov","doi":"10.1016/j.rio.2024.100750","DOIUrl":"10.1016/j.rio.2024.100750","url":null,"abstract":"<div><div>It has been shown that Sn implantation with subsequent annealing in air leads to an increase in the electroluminescence (EL) intensity of SiO₂/Si structure by two orders of magnitude. Intense violet EL with a maximum at 3.21 <!--> <!-->eV was observed at room temperature by the naked eye at forward bias. The observed emission was attributed to radiative recombination in SnO₂ nanocrystals synthesized in SiO₂ layers. The external quantum efficiency (EQE) increased with decreasing Sn concentration The maximum external quantum efficiency was found to be 0.7 % for the silica film Sn-implanted at the lowest fluence of 2.5 × 10¹⁶ <!-->cm⁻². The non-radiative charge transport (shunt current) through the sample and mechanism of EL excitation are discussed. It has been concluded that the Poole–Frenkel mechanism, or tunneling between traps are the most likely mechanisms of charge transport to light-emitting centers.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"17 ","pages":"Article 100750"},"PeriodicalIF":0.0,"publicationDate":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142441655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical investigation of graphene derivatives as HTL in PBDB-T:NCBDT bulk heterojunction organic solar cell","authors":"Denet Davis ,&nbsp;K.S. Sudheer","doi":"10.1016/j.rio.2024.100748","DOIUrl":"10.1016/j.rio.2024.100748","url":null,"abstract":"<div><div>The damaging effects of the most widely used PEDOT:PSS have led researchers to search for an alternative hole transport layer (HTL) in non-fullerene acceptor (NFA) based bulk heterojunction organic solar cells (BHJOSC’s). This work highlights the numerical simulation study of possible new approach of utilizing graphene, graphene oxide (GO), reduced graphene oxide (rGO), and p type doped graphene (p-graphene), as an alternative to PEDOT:PSS in non-fullerene acceptor based bulk heterojunction organic solar cell (NFABHJOSC) with PBDB-T as donor and NCBDT as acceptor using SCAPS1D. NCBDT is an emerging small-molecule non-fullerene acceptor (SM-NFA) whose bandgap can be tuned and reduced, making it a better option as an acceptor. Validation of the software is done by matching simulation results with experimental results. Diverse electron transport layers (ETL’s), including PDINO, ZnO, IGZO, TiO<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>:gr (20%) composite, and TiO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>:gr (10%) composite, are introduced, and device performance of various configurations is analysed. Optimization of the best device configuration ITO (4.8 eV)/rGO/PBDB-T:NCBDT/PDINO/Al gave an improved efficiency of 17.47%, fill factor (FF) of 77.45%, short circuit current density (Jsc) of 25.407 mA/cm<span><math><msup><mrow></mrow><mrow><mn>2</mn></mrow></msup></math></span>, and an open circuit voltage (Voc) of 0.8878 V.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"17 ","pages":"Article 100748"},"PeriodicalIF":0.0,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142433932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Polarization-sensitive mechanically-tunable microwave filter using metallic photonic crystals","authors":"Sanaz Zarei","doi":"10.1016/j.rio.2024.100745","DOIUrl":"10.1016/j.rio.2024.100745","url":null,"abstract":"<div><div>A tunable, polarization-sensitive microwave filter based on a reconfigurable dual-layered two-dimensional metallic photonic crystal is presented. The filter consists of a metallic plate with periodic holes and metal pillars which are anchored in a substrate material. The diameter of the pillars is smaller than that of the holes and the lateral position of the pillars with respect to the holes is tunable. We study the transmission of the device for linearly polarized electromagnetic radiation, which is polarized parallel and perpendicular to the displacement of the movable membrane, respectively. The tuning range spans from 20.18 GHz to 26.58 GHz for perpendicular polarization and from 20.18 GHz to 18.42 GHz for parallel polarization. The 3 dB operation bandwidth varies between 3.82 GHz and 6.44 GHz for perpendicular polarization and between 3.42 GHz and 3.82 GHz for parallel polarization. Experimental data are in good agreement with finite element method (FEM) simulations. The proposed structure is scalable to other frequency ranges such as terahertz frequencies.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"17 ","pages":"Article 100745"},"PeriodicalIF":0.0,"publicationDate":"2024-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142417243","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of morphology, crystal structures on the enhanced photoluminescence dynamics, zeta potential, and AC resistance of disc shaped cesium oxidex@cobalt oxide nanostructures","authors":"Vinayak Adimule ,&nbsp;Sunitha DV ,&nbsp;Rajeev Joshi ,&nbsp;A.K. Swetha ,&nbsp;Kalpana Sharma ,&nbsp;Rangappa Keri","doi":"10.1016/j.rio.2024.100742","DOIUrl":"10.1016/j.rio.2024.100742","url":null,"abstract":"<div><div>In the present study, cesium oxide_x@cobalt oxide (Cs₂O_x@Co₃O₄) (x = 5, 10 and 12 wt%) nanostructures (NS) were successfully synthesized by chemical precipitation method and characterized by XRD (X-ray diffraction), SEM (scanning electron microscope), EDX (energy dispersive X-ray), XPS (X-ray photoelectron spectroscopy), BET (Brunauer-Emmett-Teller), Raman, and UV–visible analytical techniques. XRD studies revealed the formation of the mixed phase of orthorhombic/monoclinic crystal structure. Disc shaped morphology of the cesium oxide_x@cobalt oxide NS was noticed from SEM images. Redshift in optical absorbance and decrease in optical band gap (E_g) resulted in increase in Cs¹⁺ concentration. Room temperature photoluminescence (RTPL) studies of cesium oxide_x@cobalt oxide NS at various excitation wavelengths showed sharp and broad emission peaks located at 668.2 nm (red), 675.1 nm (red), 561.8 nm (yellow-green), 834.5 nm (near infrared region), 594 nm (yellow). Steady state photoluminescence (SSPL) studies revealed a sharp emission peak at ∼ 428.0 nm (violet) with large stoke’s shift (21.1 to 590.0 eV). The zeta potential studies showed a decrease in conductance from 62 to 57 μs with an increase in mobility of the charge carriers (0.4 to 1.08 μ/s V/cm) and an increase in zeta potential (31.90 to 82.92 mV). AC resistance studies at various temperatures showed inducting coupling phenomenon in cesium oxide_x@cobalt oxide NS with DC resistance of cesium oxide_{5 wt.%}@cobalt oxide was found to be 8.2 × 10^–4 Sm^–1. The relaxation frequency of cesium oxide_{12 wt.%}@cobalt oxide NS was found be 1.2 × 10⁵ Hz. The synthesized NS is a promising candidate for optoelectronics and photonic applications.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"17 ","pages":"Article 100742"},"PeriodicalIF":0.0,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142417246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design and simulation of a highly sensitive photonic crystal fiber sensor for malaria detection","authors":"Ilhem Mired ,&nbsp;Hicham Chikh-Bled ,&nbsp;Mohammed Debbal","doi":"10.1016/j.rio.2024.100743","DOIUrl":"10.1016/j.rio.2024.100743","url":null,"abstract":"<div><div>This research focuses on developing an innovative optical sensor utilizing photonic crystal fiber with a unique cladding structure. The photonic crystal fiber’s cladding consists of four layers of circular air holes, with two of them filled with hemoglobin. This arrangement renders the photonic crystal fiber sensitive to changes in hemoglobin concentration, primarily investigating its impact on chromatic dispersion – the wavelength-dependent refractive index variation. The study analyzes two specific wavelengths, 1.2 µm and 1.4 µm, finding high sensitivity at 1.2 µm, calculated to be 0.232 ps/(nm·km)/(g/L). The potential application lies in malaria diagnosis through non-invasive blood sample analysis. We selected the refractive index of an infected red blood cell at the ring stage, setting it at n = 1.395. Our proposed sensor demonstrates outstanding performance in diagnosing malaria at an HGB concentration of 38 g/L at 1.2 µm and at an HGB concentration of 40 g/L at 1.4 µm. By monitoring hemoglobin concentration changes, this photonic crystal fiber-based sensor offers a promising method for early and accurate malaria detection, thus potentially improving global healthcare.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"17 ","pages":"Article 100743"},"PeriodicalIF":0.0,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142417245","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Displaced thinned single-mode fiber Mach-Zehnder interferometer tested for temperature and curvature applications","authors":"Leonardo J. Arevalo-Bautista ,&nbsp;Romeo Selvas-Aguilar ,&nbsp;Juan M. Sierra-Hernandez ,&nbsp;Eloisa Gallegos-Arellano ,&nbsp;Mario A. Rico-Mendez ,&nbsp;Pedro J. Fernandez de Cordoba-Castella ,&nbsp;Daniel Toral-Acosta","doi":"10.1016/j.rio.2024.100744","DOIUrl":"10.1016/j.rio.2024.100744","url":null,"abstract":"<div><div>This article explains the features and qualities of employing a thinned manufacturing fiber to assemble a Mach-Zehnder interferometer (MZI) for detecting two physical variables: temperature and curvature. The MZI comprises a filter by splicing core-offset sections of a thinned fiber (TF) cladding diameter of 80 μm in an SMF-TF-SMF configuration. The TF splices act as the arms of the MZI, while the mismatch diameter sections serve as optical fiber couplers. The optical spectrum analyzer (OSA) detects the transmitted light and analyzes its optical transmission characteristics, showing 11 peaks of modal interferences into the longitude region. As a result of the experimental arrangement, the curvature and temperature sensitivities are 0.49 nm/m⁻¹, 0.01 nm/°C, and 0.09 nm/°C for temperatures of 0–60 °C and 70–130 °C, respectively. The proposed sensor has potential advantages for measuring refractive index, pH, torsion, curvature, and temperature.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"17 ","pages":"Article 100744"},"PeriodicalIF":0.0,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142417244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Graphene coated optical microfiber for aflatoxin B1 detection","authors":"Imasda Rahmatulloh ,&nbsp;Retna Apsari ,&nbsp;Syahidatun Na’imah ,&nbsp;Tahta Amrillah ,&nbsp;Samian ,&nbsp;Dyah Hikmawati ,&nbsp;Masruroh ,&nbsp;Hendra Susanto ,&nbsp;M. Yasin ,&nbsp;Sulaiman W. Harun","doi":"10.1016/j.rio.2024.100746","DOIUrl":"10.1016/j.rio.2024.100746","url":null,"abstract":"<div><div>We proposed a graphene coated microfiber-based sensor for enhancing Aflatoxin B1 detection at room temperature. The heat-and-pull technique was used to fabricate the microfiber while the graphene layer was coated using a drop-casting technique. Aflatoxin samples are used as a sensor sensing area soaking solution, whereby the prepared graphene-coated microfiber was used as a sensor probe. The sensing is based on the modulation of transmission intensity and wavelength shift induced by the alteration of concentration of aflatoxin B1 from 0 ppm to 10 ppm. There is an increase in sensitivity from 0.129 dBm/ppm to 0.187 dBm/ppm and an increase in resolution from 0.17 ppm to 0.037 ppm by coating graphene on the microfiber sensor. For the graphene coated microfiber-based sensor, the wavelength shift from 1525.37 nm to 1525.19 nm was obtained when the aflatoxin B1 concentration was increased from 0 to 10 ppm. It reveals a sensitivity of 0.018 nm/ppm with a linearity of more than 90 %. This finding shows that the proposed sensor can be used to detect various concentration of Aflatoxin sample with the ability to offer real time measurement.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"17 ","pages":"Article 100746"},"PeriodicalIF":0.0,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142417241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Overlooked effects of wavefront reception with or without speed limit, from aberration to time measurement","authors":"Denis Michel","doi":"10.1016/j.rio.2024.100741","DOIUrl":"10.1016/j.rio.2024.100741","url":null,"abstract":"<div><div>A general approach to wavefront reception applicable to any type of wave allows to point out some overlooked aspects and ignored consequences of established theories. The Doppler and aberration effects of electromagnetic waves, the cosmological redshift and the measurement of durations are all perceptual phenomena, and as such require the use of reception rather than Lorentz-transformed coordinates, since perceived durations relate proper to proper durations whereas the famous time dilation of special relativity relates proper to improper durations. Taking this subtlety into account rehabilitates the controversial Poincaré ellipsoid whose polar equation is just the relativistic Doppler effect. The application of this approach to the Galilean case whose transformed and received wavefronts are homothetic, reveals new aberration relations and the existence of a transverse Doppler effect very similar, in proportion to the respective wave velocities, to the relativistic one, thus forbidding in practice the test of his theory proposed by Einstein. The reasons for the long persistence of a classical angular Doppler formula divorced from wavefront reception are discussed, one of them ironically being the theory of special relativity.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"17 ","pages":"Article 100741"},"PeriodicalIF":0.0,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142417242","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A holistic understanding of optical properties in amorphous H-terminated Si-nanostructures: Combining TD-DFT with AIMD","authors":"","doi":"10.1016/j.rio.2024.100694","DOIUrl":"10.1016/j.rio.2024.100694","url":null,"abstract":"<div><p>Silicon, traditionally known as an indirect band gap semiconductor, unveils intriguing properties at the nanoscale, stemming from deviations from k-conservation rules within nanostructures. In our study, we scrutinized four hydrogenated Si 0D-nanostructures—Si₁₀H₁₆, Si₁₄H₂₀, Si₁₈H₂₄, and Si₂₂H₂₈—to unravel their dynamic stability under thermal fluctuations and optical characteristics. We initiated our exploration by employing the TD-DFT framework to generate and analyze the optical properties of these geometrically optimized nanostructures. Simultaneously, we conducted ab initio molecular dynamics simulations to examine the structural robustness and thermal stability of the four structures. Leveraging the Car-Parrinello molecular dynamics approach within the Quantum ESPRESSO open software suite, we observed temperature evolution and stability differences among the nanostructures at targeted temperatures 40 and 300 K. Our subsequent investigation delved into the Turbo-Lanczos time-dependent DFT method, unraveling the optical properties and excited-state dynamics of hydrogenated Si nanostructures. The results unveiled shifts towards higher energy absorption edges E₀, accompanied by alterations in the permittivity tensor, complex refractive index, oscillator strength, and reflectivity. Notably, the analysis revealed an enlarged HOMO-LUMO gap, distinctive from bulk Si. Furthermore, our models predicted the elimination of phase-dependent E₁/E₂ optical transition peaks in the imaginary part of the dielectric function, and a gradual decrease in the low-frequency dielectric response with increased hydrogenation of the amorphous structures. These findings underscore the promising applications of hydrogenating Si nanostructures in diverse technological domains such as optoelectronics, memristors, sensors, and quantum computing. Their tunable optical properties, size-dependent behaviors, and compatibility with existing silicon-based devices make them particularly appealing for next-generation technologies.</p></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"16 ","pages":"Article 100694"},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666950124000919/pdfft?md5=4bf3d55996d866e8ab8438667092ded7&pid=1-s2.0-S2666950124000919-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141139956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fabrication of a hot mirror using ITO-free electrochromic films","authors":"Chao-Te Lee ,&nbsp;Hung-Pin Chen ,&nbsp;Wei-Chun Chen ,&nbsp;Jing-Han Xie ,&nbsp;Cheng-Chung Jaing","doi":"10.1016/j.rio.2024.100735","DOIUrl":"10.1016/j.rio.2024.100735","url":null,"abstract":"<div><p>In this study, WO₃/Ag/W/WO₃ (WAWW) films were deposited at room temperature on a B270 glass substrate from W and Ag targets using a radiofrequency magnetron reactive sputtering system. The influence of the thin tungsten interlayer on the electrical and optical properties of the WAWW layer structure was investigated through ellipsometry, a four-point probe and a spectrophotometer. It was determined that the thin tungsten interlayer effectively prevented the oxidation of the silver film. The WAWW film had a dielectric-metal-dielectric (DMD) layered structure with good electrical conductivity and high visible transmittance. The tungsten layer was no more than 2-nm thick. The sheet resistance and luminous transmittance of the WO₃(29.5 nm)/Ag(14.2 nm)/W(2 nm)/WO₃(68.6 nm) film were 4.64 Ω/sq and 65.4 %, respectively. Based on the WAWW four-layer structure, stacked WO₃(29.5 nm)/Ag(14.2 nm)/W(2 nm)/WO₃(68.6 nm)/Ag(16.9 nm)/W(2 nm)/WO₃(30.4 nm) seven-layer structures deposited on B270 glass substrates were used for both ITO-free electrochromic and hot mirror applications. The visible (400–700 nm) and NIR (700–1200 nm) transmittance values of the bleached WAWW seven-layer structure were 71.5 % and 9.9 %, respectively. The visible transmittance of the colored WAWW seven-layer structure was 23.6 %. Finally, the bi-layer WAWW films were used to obtain an ITO-free WAWW seven-layer structure with a good electrochromic and optical performance.</p></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"16 ","pages":"Article 100735"},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666950124001329/pdfft?md5=561d996ca8def2e41e1e3dd140f48e84&pid=1-s2.0-S2666950124001329-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142117274","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}