Ketavath Kumar Naik , Chirukuri Naga Phaneendra , Tathababu Addepalli , Ahmed J.A. Al-Gburi
{"title":"Quad-port wheel-shaped MIMO patch antenna system deployed at UWB application for 6G terahertz communications","authors":"Ketavath Kumar Naik , Chirukuri Naga Phaneendra , Tathababu Addepalli , Ahmed J.A. Al-Gburi","doi":"10.1016/j.photonics.2025.101430","DOIUrl":"10.1016/j.photonics.2025.101430","url":null,"abstract":"<div><div>A quad-port wheel-shaped MIMO patch (QWMP) antenna featuring a circular complementary split-ring resonator (CSRR) slot is proposed for 6G terahertz communication. The radiating elements are configured in a pattern diversity arrangement to enhance diversity performance and minimize mutual coupling. The QWMP antenna is fabricated on Kapton polyimide with overall dimensions of 400 × 400 × 20 µm³ . It exhibits a wide bandwidth (S₁₁ < −10 dB) of 0.94 THz, covering the range from 1.93 THz to 2.87 THz. The QWMP antenna achieves a high gain of 8.12 dBi and 9.41 dBi at 2.00 THz and 2.75 THz, respectively. The values of ECC < 0.001 and DG > 9.995 indicate that the QWMP antenna has excellent diversity performance, making it suitable for high-speed, low-latency 6 G communication systems. The simulated results of key antenna parameters, including radiation patterns, gain, and diversity characteristics, are examined and presented. The proposed antenna demonstrates significant potential for next-generation terahertz communication applications.</div></div>","PeriodicalId":49699,"journal":{"name":"Photonics and Nanostructures-Fundamentals and Applications","volume":"66 ","pages":"Article 101430"},"PeriodicalIF":2.5,"publicationDate":"2025-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144711508","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}
A. Sohrabi, M. Asadolah Salmanpour, M. Mosleh, S.M. Hamidi
{"title":"Exploring the interaction between bloch surface waves and atomic hot vapor: a theoretical perspective","authors":"A. Sohrabi, M. Asadolah Salmanpour, M. Mosleh, S.M. Hamidi","doi":"10.1016/j.photonics.2025.101429","DOIUrl":"10.1016/j.photonics.2025.101429","url":null,"abstract":"<div><div>The miniaturization of atom-light interaction platforms is crucial for advancing modern optical technologies, enabling significant improvements in sensing, communication, and quantum information processing. In this paper, we present a theoretical investigation into the coupling of Bloch surface waves (BSWs) at the resonance angle of 69° in a one-dimensional 24-layered photonic crystals with atomic hot vapor with a focus on atomic structures. These surface waves are known for their strong field confinement and high sensitivity to environmental changes which offer a promising avenue for enhancing light-matter interactions at reduced scales. Our findings highlight the potential of Bloch surface waves to enhance and control the localized density of states (LDOS), thereby improving the resolution of atomic transition lines. Notably, our simulations demonstrate that BSWs achieve superior resolution compared to plasmonic modes, enabling the distinct resolution of all eight hyperfine states of natural rubidium vapor (four for <sup>85</sup>Rb and four for <sup>87</sup>Rb D<sub>1</sub> line). This study underscores the importance of integrating Bloch surface waves with atomic hot vapor for developing next-generation miniaturized optical devices, which can lead to breakthroughs in precision metrology, high-resolution spectroscopy, and quantum technologies.</div></div>","PeriodicalId":49699,"journal":{"name":"Photonics and Nanostructures-Fundamentals and Applications","volume":"66 ","pages":"Article 101429"},"PeriodicalIF":2.5,"publicationDate":"2025-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144694923","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}
Wenyuan Zhang , Xin Liu , Yuan Tian , Mingda Zhang , Binzhao Cao , Yibiao Yang , Hongming Fei , Fei Sun , Yichao Liu , Zhihui Chen
{"title":"Simultaneous excitation and directional emission enhancements of upconversion fluorescence enabled by optical Tamm plasmon in hybrid structure with metal-photonic crystal and grating","authors":"Wenyuan Zhang , Xin Liu , Yuan Tian , Mingda Zhang , Binzhao Cao , Yibiao Yang , Hongming Fei , Fei Sun , Yichao Liu , Zhihui Chen","doi":"10.1016/j.photonics.2025.101428","DOIUrl":"10.1016/j.photonics.2025.101428","url":null,"abstract":"<div><div>Metal-dielectric hybrid structures have become ideal platforms for enhancing fluorescence emission due to their ability to support strong resonances. This study presents a dual-resonance Tamm plasmon (TP) configuration integrating a one-dimensional photonic crystal (1DPC) with precisely optimized metallic gratings. By utilizing the synergistic COBYLA (Constrained Optimization BY Linear Approximations) algorithm, this design achieves comprehensive far-field enhancement of upconversion nanoparticles (UCNPs) fluorescence through synergistic excitation and emission manipulation. By exciting the optical Tamm mode within the structure, the hybrid structure successfully forms a strong localized electromagnetic field, benefiting excited-state absorption (ESA) with angle-insensitive excitation enhancement for both TE and TM polarizations. The far-field fluorescence emission enhancement was achieved for two different orientations of UCNPs. Notably, the maximum overall far-field enhancement factor reaches 1.04× 10<sup>5</sup>-folds for <em>x</em>-orientation UCNPs, taking into account the effects of relaxation during the excitation process. Additionally, the results indicate that introducing the grating into the TP structure leads to an angular <em>FWHM</em> of 18.7°, which plays a crucial role in confining far-field radiation and enhancing fluorescence collection efficiency, thereby promoting highly directional emission. This TP-based platform demonstrates exceptional stability and multi-modal enhancement capability, holding substantial promise for advanced photonic applications including single-molecule biosensing, upconversion lighting, and other photon-based technologies that require high stability and substantial enhancement.</div></div>","PeriodicalId":49699,"journal":{"name":"Photonics and Nanostructures-Fundamentals and Applications","volume":"66 ","pages":"Article 101428"},"PeriodicalIF":2.5,"publicationDate":"2025-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144657214","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}
Madhupriya Ganesh , Nagarajan Nallusamy , R. Vasantha Jayakantha Raja , N. Arzate-Plata , Krishnamoorthy Pandiyan , Rakesh Kumar Karn
{"title":"Ultra-compact ferrofluid infiltrated magnetic field sensor utilizing microring resonator in silicon-on-insulator platform","authors":"Madhupriya Ganesh , Nagarajan Nallusamy , R. Vasantha Jayakantha Raja , N. Arzate-Plata , Krishnamoorthy Pandiyan , Rakesh Kumar Karn","doi":"10.1016/j.photonics.2025.101424","DOIUrl":"10.1016/j.photonics.2025.101424","url":null,"abstract":"<div><div>In this paper, we aim to propose a compact high Q-factor magnetic field sensor which is CMOS compatible. Hence, we have proposed a novel micro-ring resonator (MRR) design using a silicon-on-insulator (SOI) platform where a magnetic ferrofluid is filled in the slot cavity. First, we initiated the design of slotted MRR for maximal light confinement by tuning the dimensions of rail widths, height, and slot width. After optimization, the rail width of 250 nm and the slot width of 100 nm with a height of 220 nm are reported to have a maximal confinement factor, forming the base design of the proposed magnetic field sensor. The application of an external magnetic field to the slotted MRR device with a ring radius of <span><math><mrow><mn>50</mn><mspace></mspace><mi>μ</mi><mi>m</mi></mrow></math></span> resulted in a considerable change in the effective index, leading to significant variations in phase and transmission characteristics. A sensitivity of 5.399 pm/Oe is observed through consecutive dips in the transmission characteristics for the proposed model. To design an efficient magnetic sensor, the qualitative analysis, namely the quality factor (Q-factor) and extinction ratio (ER) are optimized by using rail widths and slot width. The reported results infer that the dimension of rail widths of 250 nm and slot width of 125 nm offer a high Q-factor of approximately 6.5 <span><math><mo>×</mo></math></span> 10<sup>4</sup> with an ER of 37 dB. The results pave the way for further advancements in integrated photonics and magnetic field manipulation.</div></div>","PeriodicalId":49699,"journal":{"name":"Photonics and Nanostructures-Fundamentals and Applications","volume":"66 ","pages":"Article 101424"},"PeriodicalIF":2.5,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144657215","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}
Fozlur Rayhan , Md Hamidur Rahman , Sohel Rana , Dipika Das Ria , Jannati Islam Chy , Md Shakib Hosen , Tanzir Ahamed , Jerry Sarpong , Kelly Yegbe , Md Shihab Uddin
{"title":"Unveiling the potential of non-toxic Ge based perovskite material for all inorganic solar cells using multiple ETLs","authors":"Fozlur Rayhan , Md Hamidur Rahman , Sohel Rana , Dipika Das Ria , Jannati Islam Chy , Md Shakib Hosen , Tanzir Ahamed , Jerry Sarpong , Kelly Yegbe , Md Shihab Uddin","doi":"10.1016/j.photonics.2025.101425","DOIUrl":"10.1016/j.photonics.2025.101425","url":null,"abstract":"<div><div>This study optimizes all-inorganic Pb-free CsGeI<sub>3</sub>-based perovskite solar cells. CsGeI<sub>3</sub> forms four structures with four electron transport layers (ZnOS, BaSnO<sub>3</sub>, PC<sub>61</sub>BM, and ZnSe) and one hole transport layer of Copper Tin Ferrite Sulfide (CFTS). The thickness of the absorber layer is optimized by assessing the effects of the electron transport layer and hole transport layer thicknesses, along with the acceptor and defect densities in the absorbers, donor and defect densities in the electron transport layers, and acceptor and defect densities in the hole transport layers. After optimization, the FTO/ZnOS/CsGeI<sub>3</sub>/CFTS/Au configuration achieved optimal performance with a <em>V</em><sub>OC</sub> of 1.07 V, <em>J</em><sub>SC</sub> of 24.39 mA/cm², FF of 82.49 % and efficiency of 21.72 %. The influences of series and shunt resistance, temperature, voltage-current density, quantum efficiency, and generation and recombination rates are examined to determine structural stability. This study aims to improve understanding of CsGeI<sub>3</sub>-based perovskite solar cell’s experimental research potential.</div></div>","PeriodicalId":49699,"journal":{"name":"Photonics and Nanostructures-Fundamentals and Applications","volume":"66 ","pages":"Article 101425"},"PeriodicalIF":2.5,"publicationDate":"2025-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144623412","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}
Yafei Hou , Wenjun He , Songquan Yan , Zepeng Wu , Yi Liu , Yajun You , Jian He , Xiujian Chou
{"title":"Inter-mode backward stimulated Brillouin scattering in lithium niobate core fiber","authors":"Yafei Hou , Wenjun He , Songquan Yan , Zepeng Wu , Yi Liu , Yajun You , Jian He , Xiujian Chou","doi":"10.1016/j.photonics.2025.101426","DOIUrl":"10.1016/j.photonics.2025.101426","url":null,"abstract":"<div><div>Brillouin sensing in multimode optical fibre enables the simultaneous modal transmission of multiple modulus, such as temperature and strain, and helps to promote the development of simultaneous multi-property sensing techniques. Among these, intermodal backward Brillouin scattering induced by higher order modes (HOMs) is of great importance for understanding the phonon-photon interaction in multimode fibre. In addition, lithium niobate (LiNbO<sub>3</sub>) materials have potential applications in sensing due to their excellent electro-optical properties, which are expected to provide higher sensitivity and accuracy. In this paper, the inter-mode BSBS induced by higher order optical modes in micron scale LiNbO<sub>3</sub> optical fibre is investigated. The inter-mode excited Brillouin scattering characteristics of the first 10 LP modes in the fibre are simulated and analysed by finite element simulation. During backward Brillouin scattering, several longitudinal acoustic modes (LAMs) are excited. However, only a few specific low-order LAMs are involved in the interaction between different optical mode pairs, resulting in Brillouin amplification. In this paper, we elucidate the differences in the gain characteristics of the Brillouin gain spectra between different modes and reveal the acoustic mode law that contributes most to the BGS in the inter-mode BSBS. The results show that both the effective refractive index (2.1847–2.2072) and the Brillouin scattering frequency shift (20.6–20.9 GHz) decrease with the increase of mode order in this structure. And the Brillouin gain reaches 0.4244 m<sup>−1</sup>·W<sup>−1</sup>, which is a significant improvement compared with the conventional SiO<sub>2</sub> fiber, predicting the improvement of sensitivity in sensing.</div></div>","PeriodicalId":49699,"journal":{"name":"Photonics and Nanostructures-Fundamentals and Applications","volume":"66 ","pages":"Article 101426"},"PeriodicalIF":2.5,"publicationDate":"2025-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144579297","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}
Ruijie Xie , Aodi Shi , Fanghao Shui , Hengdi Wang , Xiaokang Yang
{"title":"Research on light absorption efficiency of P3HT:PCBM-based solar cells improved by triple grating structure","authors":"Ruijie Xie , Aodi Shi , Fanghao Shui , Hengdi Wang , Xiaokang Yang","doi":"10.1016/j.photonics.2025.101380","DOIUrl":"10.1016/j.photonics.2025.101380","url":null,"abstract":"<div><div>In this paper, a novel triple-layer grating structure is proposed to improve light absorption efficiency of P3HT:PCBM-based solar cell. The periodic Ag grating is fabricated at bottom of P3HT:PCBM photosensitive layer and Ag electrode to excite surface plasmons (SPs). The excited SPs can greatly enhance electromagnetic field intensity around Ag grating, which can improve chance and efficiency of interaction between photons and photosensitive layer, and enhance light absorption efficiency of solar cell. The periodic indium tin oxide (ITO) grating and PEDOT:PSS grating is fabricated by etching rectangular grooves on top of ITO layer and depositing PEDOT:PSS layer. The light-trapping effect generated by grating allows light to be reflected and refracted multiple times inside solar cell, which can further increase chance of interaction between photons and photosensitive layer, and enhance light absorption efficiency of solar cell. The COMSOL software is used to simulate and optimize parameters of the novel structure. The light reflectivity, light transmissivity and metal absorption loss of photons at different structural parameters are obtained, and the light absorption efficiency is calculated. The simulation results show that light absorption efficiency of the novel structure is almost above 90 % at wavelength range of 400–500 nm in TM mode and almost above 90 % at wavelength range of 450–500 nm in TE mode. This research provides a reliable foundation for development of the novel P3HT:PCBM-based solar cell with high light absorption efficiency.</div></div>","PeriodicalId":49699,"journal":{"name":"Photonics and Nanostructures-Fundamentals and Applications","volume":"66 ","pages":"Article 101380"},"PeriodicalIF":2.5,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144518887","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}
Hang Sun , Zheng-Da Hu , Jingjing Wu , Jicheng Wang
{"title":"Design of robust topological edge states clock-shaped multiplexer in anisotropic photonic crystals enhanced by neural networks","authors":"Hang Sun , Zheng-Da Hu , Jingjing Wu , Jicheng Wang","doi":"10.1016/j.photonics.2025.101423","DOIUrl":"10.1016/j.photonics.2025.101423","url":null,"abstract":"<div><div>Topological edge states have demonstrated significant potential in controlling light propagation. This paper presents a high-degree anisotropic photonic crystal based on a combination of convolutional and fully connected neural networks. The model accurately predicts the asymmetry parameters and band structure in both directions. We achieve topological edge state transmission over a broader frequency range compared to traditional valley photonic crystal array channels. We precisely predict accurate results for both wide-frequency boundary state outputs and topological bandgaps. We design a clock-shaped wavelength division multiplexer to enable precise optical channel selection. Our deep learning model demonstrates robust performance against input variations, and the structure remains highly resilient to disturbances. The deep learning-assisted anisotropic structure demonstrates precise selectivity, wideband high-intensity transmission and strong robustness in topological edge states significantly enhancing the application potential and development efficiency of topological edge states.</div></div>","PeriodicalId":49699,"journal":{"name":"Photonics and Nanostructures-Fundamentals and Applications","volume":"66 ","pages":"Article 101423"},"PeriodicalIF":2.5,"publicationDate":"2025-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144330394","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}
Shaoyu Jia , Lida Li , Mingjian Ma , Shuguang Li , Hailiang Chen
{"title":"High-resolution fiber laser sensor for strain and temperature measurements using matrix demodulation","authors":"Shaoyu Jia , Lida Li , Mingjian Ma , Shuguang Li , Hailiang Chen","doi":"10.1016/j.photonics.2025.101421","DOIUrl":"10.1016/j.photonics.2025.101421","url":null,"abstract":"<div><div>Structural health monitoring demands high-resolution and demodulation measurements of strain and temperature simultaneously. Here, we propose an erbium-doped fiber ring laser (EDFRL) which is integrated with a polarization maintaining fiber inserted Sagnac interferometer (PMF-SI) and a fiber Bragg grating (FBG) to achieve this purpose. Leveraging the narrow full width at half maximum (FWHM) and high coherence of the EDFRL, the proposed sensor achieves ultrahigh resolution (<em>R</em>) of 0.015 °C for temperature measurement and 1.96 με for strain measurement respectively, surpassing most reported fiber laser-based sensors. A matrix is utilized to decouple the cross-sensitivity between temperature and strain owing to the e differential responses of PMF-SI and FBG. The detection errors are < 0.183 °C for temperature measurement and < 15 με for strain measurement, respectively. Owing to the high-resolution and decoupling method, the proposed sensor can measure temperature and strain simultaneously with good performance.</div></div>","PeriodicalId":49699,"journal":{"name":"Photonics and Nanostructures-Fundamentals and Applications","volume":"66 ","pages":"Article 101421"},"PeriodicalIF":2.5,"publicationDate":"2025-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144298821","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}
Zhenyuan Wang , Heyang Qin , Zheng-Da Hu , Wenyuan Wang , Tianhang Chen , Jingjing Wu , Jicheng Wang
{"title":"Switchable fractional perfect composite vortex encryption based on double-layer metasurface","authors":"Zhenyuan Wang , Heyang Qin , Zheng-Da Hu , Wenyuan Wang , Tianhang Chen , Jingjing Wu , Jicheng Wang","doi":"10.1016/j.photonics.2025.101422","DOIUrl":"10.1016/j.photonics.2025.101422","url":null,"abstract":"<div><div>We propose a double-layer metasurface to realize the polarization switching of fractional perfect composite vortex beams (FPCVBs). The metasurface is designed by the Jones matrix formalism and optimized through the “Random Forest” machine learning algorithm, achieving high polarization switching efficiency. The grafted-FPCVBs are presented with featuring multivariate topological charges, and double-ring FPCVBs are achieved with independent on/off modulation and shaping transformation of inner and outer ring intensities. These capabilities unlock orbital angular momentum density modulation and light field reconfiguration in composited light architectures. Moreover, we design an optical encryption protocol inspired by the hierarchical structure of chinese characters, where semantic radicals are mapped to polarization-encoded FPCVBs. These innovations present significant potential for applications in optical information security, particle manipulation, and next-generation photonic communications.</div></div>","PeriodicalId":49699,"journal":{"name":"Photonics and Nanostructures-Fundamentals and Applications","volume":"66 ","pages":"Article 101422"},"PeriodicalIF":2.5,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144314567","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}