Optics Communications最新文献

{"title":"Inverse design of photonic crystal fibers for dispersion engineering using neural networks","authors":"Daniel Rodriguez-Guillen ,&nbsp;Antonio Díez ,&nbsp;Miguel V. Andrés ,&nbsp;Lorena Velazquez-Ibarra","doi":"10.1016/j.optcom.2025.131891","DOIUrl":"10.1016/j.optcom.2025.131891","url":null,"abstract":"<div><div>This work presents a novel approach for the inverse design of photonic crystal fibers, by implementing neural networks to engineer dispersion profiles. We investigate two neural network architectures — inverse neural networks and tandem neural networks — across three configurations: a direct inverse neural network, a tandem neural network, and an optimized inverse neural network. Our results show that the optimized inverse neural network achieves superior performance without the need for a complex tandem architecture. By using five strategically selected data points from the dispersion spectrum, the design process is streamlined, enabling accurate predictions with minimal input data. Neural network predictions are validated through finite-difference frequency-domain simulations and further confirmed by experimental chromatic dispersion measurements. Additionally, we evaluate the tolerance error on the dispersion curve due to defects introduced during the stack-and-draw process and demonstrate the versatility of the neural networks in modeling various physical phenomena with fast and straightforward designs. While focused on photonic crystal fibers, this methodology can be extended to other photonic structures, such as integrated waveguides optimized for specific optical properties. Our findings highlight the potential of neural networks for efficient, precise inverse design in diverse photonic applications.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"587 ","pages":"Article 131891"},"PeriodicalIF":2.2,"publicationDate":"2025-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143923879","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":"Optimizing parameters to enhance photovoltaic performance of Ce1-AZnAO2/ CeMnO2/MAFASnBrI/BaSi2 solar cells","authors":"Ravi Pushkar ,&nbsp;Amit Prakash ,&nbsp;Raushan Kumar","doi":"10.1016/j.optcom.2025.131959","DOIUrl":"10.1016/j.optcom.2025.131959","url":null,"abstract":"<div><div>The efficiency of multilayer solar cells is often hindered by the improper selection of high energy bandgap materials, interfacial defects, and recombination losses, all of which limit charge carrier mobility and overall performance. This study aims to enhance the photovoltaic performance of a Ce_1-AZn_AO₂/CeMnO₂/MAFASnBrI/BaSi₂ solar cell by incorporating CeZnO₂ as a high energy bandgap electron transport layer material (ETLM) and BaSi₂ as a high energy bandgap hole transport layer material (HTLM), along with strategic optimization of defect parameters. Using numerical simulations, we investigated the impact of energy levels, layer thicknesses, defect densities, and recombination rates across key interfaces. The doping concentration of Zn in Ce_1-AZn_AO₂was adjusted to reduce trap-assisted recombination and enhance carrier mobility. Simultaneously, the CeMnO₂ layer was optimized for thickness and interface passivation to improve carrier selectivity. Modifications to the MAFASnBrI₃ photoactive layer promoted balanced charge transport and improved optical absorption, while the BaSi₂ substrate supported efficient carrier collection. Simulation results revealed a substantial improvement in power conversion efficiency (PCE), achieving values above 28.74 %, along with enhanced open-circuit voltage (Voc) and fill factor (FF). These outcomes highlight the effectiveness of defect engineering in advancing high-efficiency, next-generation photovoltaic technologies.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"590 ","pages":"Article 131959"},"PeriodicalIF":2.2,"publicationDate":"2025-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143947651","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":"Evaluating the accuracy of color vision deficiency simulation: Methodologies and a comparative analysis of current models","authors":"Xiaojie Zhao ,&nbsp;Boyang Fu ,&nbsp;Zhenxing Li ,&nbsp;Chengya Lu ,&nbsp;Qi Dai","doi":"10.1016/j.optcom.2025.131961","DOIUrl":"10.1016/j.optcom.2025.131961","url":null,"abstract":"<div><div>Color vision deficiency (CVD) simulation seeks to approximate the color perception of color-deficient observers (CDOs) for color-normal observers (CNOs). This technique provides a basis for developing color-enhancement technologies aimed at helping CDOs overcome challenges in color-dependent and visualization-related tasks. However, the accuracy of current CVD simulation models remains unclear, and an effective evaluation method is lacking. In this study, we propose an evaluation method based on the quantification of color vision tests for both CDOs and CNOs. Specifically, the accuracy of a simulation model is evaluated by comparing the test results of CDOs viewing original colors and CNOs viewing model-simulated colors. Our human-factor study demonstrates that the proposed method can effectively evaluate the accuracy of CVD simulation models. Specifically, the Machado and Yaguchi models significantly outperform the Yang model in simulating the color perception of CDOs, revealing the dominant influence of the stage theory in human color vision on simulation accuracy. Moreover, our findings indicate that the decline in color discrimination ability caused by CVD is not linearly correlated with the severity of the deficiency. Minor and moderate shifts in spectral sensitivity have very limited impacts on individuals’ actual color perception. These findings can contribute to the advancement of CVD simulation models and support their applications in enhancing the color vision of CDOs.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"587 ","pages":"Article 131961"},"PeriodicalIF":2.2,"publicationDate":"2025-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143934757","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":"SNR improvement for Φ-OTDR with improved adaptive non-local means denoising method","authors":"Weiming Zeng,&nbsp;Yizheng Sun,&nbsp;Hengwei Shen,&nbsp;Wen Chen,&nbsp;Jing Liu,&nbsp;Yushan Chen,&nbsp;Zhichun Fan","doi":"10.1016/j.optcom.2025.131914","DOIUrl":"10.1016/j.optcom.2025.131914","url":null,"abstract":"<div><div>An improved adaptive non-local means (NLM) denoising method, called side window NLM (SW-NLM), was proposed in this study. Unlike the centrally symmetric square windows used in traditional NLM filtering, the SW-NLM method utilized rectangular side windows to further improve the signal-to-noise ratio (SNR) of phase-sensitive optical time domain reflectometer (<span><math><mi>Φ</mi></math></span>-OTDR). Additionally, SW-NLM method incorporated adaptive parameter estimation by calculating the SNR of the filtered traces and optimizing smoothing coefficients and window sizes accordingly. SW-NLM algorithm increased the SNR by up to 45.85 dB, achieving a 25.5% improvement over the NLM filtering while better preserving effective vibration information through the side window technique. Moreover, SW-NLM was applied to dual vibration condition to validate its capability of multipoint detection. This work contributes to enhancing the performance of <span><math><mi>Φ</mi></math></span>-OTDR and improving its signal recognition capability.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"587 ","pages":"Article 131914"},"PeriodicalIF":2.2,"publicationDate":"2025-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143912366","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":"Control and optimization of absorbing behavior in graphene-based multiple narrowband metamaterial absorber by machine learning","authors":"Jiaxuan Xue ,&nbsp;Cheng Chen ,&nbsp;Shilei Tian ,&nbsp;Huiyao Zhang ,&nbsp;Jixin Wang ,&nbsp;Wu Zhao ,&nbsp;Zhiyong Zhang ,&nbsp;Johan Stien","doi":"10.1016/j.optcom.2025.131958","DOIUrl":"10.1016/j.optcom.2025.131958","url":null,"abstract":"<div><div>Graphene, with its tunable properties and high optical response characteristics, has a wide range of applications in the development of metamaterial absorbers: it is frequently employed as a substitute for the periodic metal structure of conventional metamaterial devices, or utilized as an intermediate layer to composite with the devices. However, precise control over absorption performance within specific narrowbands and the optimization of multi-peak absorption intensity remain key challenges. In this study, a machine learning approach is integrated into the device design process to develop a multilayer heterogeneous composite metamaterial absorber based on graphene, effectively addressing these issues. By combining a patterned metal layer, a graphene thin film layer, and a metal enhancement layer with two dielectric layers and a metallic ground plane, multi-narrowband resonance is successfully achieved. Firstly, machine learning supervision is utilized to effectively control the device's multi-narrowband absorption behaviors within the 0.5–1.2 THz frequency range, leading to the realization of double-peak, triple-peak, and quadruple-peak multi-narrowband absorption behaviors, respectively. Then, leveraging the predictive capabilities of the machine learning model, the structural parameters of the device are tuned to achieve comprehensive optimization of its multi-narrowband absorption performance. As a result, the absorption performance across multiple frequency ranges exceeds 90 %. This method avoids the traditional trial-and-error optimization and provides a scalable design framework for customized multi-narrow band high-performance terahertz absorber.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"587 ","pages":"Article 131958"},"PeriodicalIF":2.2,"publicationDate":"2025-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143916479","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":"High sensitivity fiber optic ultraviolet light and temperature sensor based on Fabry-Perot cavity fabricated by MA-POSS material","authors":"Li Li,&nbsp;Chao Jiang,&nbsp;Xiaoshan Guo,&nbsp;Simei Sun,&nbsp;Tingshui Cao,&nbsp;Tianqi Yan,&nbsp;Jian Wen,&nbsp;Huiling Huang","doi":"10.1016/j.optcom.2025.131956","DOIUrl":"10.1016/j.optcom.2025.131956","url":null,"abstract":"<div><div>In order to meet the demand for high-sensitivity UV light detection in industrial production, a novel Ultraviolet (UV) light and temperature sensor based on Fabry-Perot interferomwter (FPI) and harmonic vernier effect is proposed. Firstly, the MA-POSS liquid is dropped into the gap between two aligned single-mode fibers (SMFs), and then the MA-POSS is irradiated with UV lamp for more than 10 s. After liquid curing, a MA-POSS based FPI is made and named FPI₁. When FPI₁ is irradiated with UV light, the refractive index of MA-POSS changes and it expands along the longitudinal line, resulting in linear drift of the resonant wavelength of FPI₁. The UV light intensity is obtained by demodulating the resonant wavelength of FPI₁. Additionally, MA-POSS also has good thermal sensitivity, so FPI₁ is highly sensitive to temperature. To further enhance sensitivity, a reference FPI₂ was prepared by sequentially fusion splicing SMF - capillary - SMF, resulting in a free spectral range of only about half of FPI₁. When FPI₁ and FPI₂ are cascaded, they form a first harmonic vernier effect sensor S₁. The experimental studies have found that the sensitivities of UV light intensity and temperature of FPI₁ are 9.6 pm/(mW/cm²) and 133.1 pm/°C respectively, and the sensitivities of UV light intensity and temperature of S₁ are −396.5 pm/(mW/cm²) and −4.6277 nm/°C respectively. S₁ amplified the UV light intensity and temperature sensitivity of FPI₁ by 42.4 and 35.3 times respectively. In summary, the proposed sensor can achieve high sensitivity measurement of UV light intensity and temperature simultaneously, and the sensor structure is simple, compact, easy to manufacture, and robustness. It will become one of the strong competitors in UV intensity detection.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"587 ","pages":"Article 131956"},"PeriodicalIF":2.2,"publicationDate":"2025-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143923440","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":"Asymmetric multi-image encryption technology based on position multiplexing and computer-generated holography","authors":"Yuan Deng ,&nbsp;Yu Peng ,&nbsp;Xingjiang Han ,&nbsp;Weimin Jin ,&nbsp;Taiyan Zhou ,&nbsp;Zichen Zhao ,&nbsp;Yong Li ,&nbsp;Lihong Ma","doi":"10.1016/j.optcom.2025.131960","DOIUrl":"10.1016/j.optcom.2025.131960","url":null,"abstract":"<div><div>The multi-image encryption method has the advantage of large information encryption capacity, which is conducive to the development of high-throughput cryptosystems. This paper proposes an asymmetric multi-image encryption and decryption technique based on position multiplexing and computer-generated holography (CGH). In the proposed encryption scheme, each channel adopts the phase-truncated asymmetric encryption method using double random phase encoding in the Fresnel domain with position multiplexing to encrypt a plaintext image. Then the complex amplitude distributions from each channel are superposed together and phase-truncated, which is further encrypted by off-axis CGH to obtain the final ciphertext. Additionally, to solve the problem of crosstalk noise in the decryption of multiple images, a new decryption framework is proposed. A constrained complex total variation (TV) regularizer, which explores the well-known sparsity in the gradient domain, and the implicit image prior from advanced denoisers, are introduced to enhance the well posedness of the nonconvex problem under limited measurements, and two-step iterative shrinkage-thresholding (TwIST) algorithm is used to accelerate the iterations. The system can flexibly encrypt and decrypt multi-frame images, <em>e.g.</em>, in the case of encrypting four complex grayscale images, the decrypted plaintext images achieved an average correlation coefficient (CC) of 0.9938 and an average peak signal-to-noise ratio (PSNR) of 31.10 dB. The results demonstrate that the proposed encryption scheme not only efficiently achieves the encryption of multi-frame complex grayscale images, but also offers certain advantages concerning high encryption capacity, a large key space, flexible system parameter settings, and robust resistance against attacks.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"587 ","pages":"Article 131960"},"PeriodicalIF":2.2,"publicationDate":"2025-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143923533","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":"Influence of slab interfaces and modulation regime on isolation ratio in graphene space-time crystal slabs: towards high-performance isolation","authors":"Kang-Hyok O,&nbsp;Kwang-Hyon Kim","doi":"10.1016/j.optcom.2025.131957","DOIUrl":"10.1016/j.optcom.2025.131957","url":null,"abstract":"<div><div>Nonreciprocal devices based on dynamic modulation play a crucial role in on-chip light control such as optical isolation. In this work, we propose new ways for improving isolation performances in space-time crystal slabs by investigating the influence of slab interfaces and modulation regime, taking graphene plasmonic space-time crystals, as examples. First, we show that when slab is truncated by interfaces with the velocity the same as modulation interface, no Bloch-Floquet mode is excited inside the slab by forward incident pulse with central frequency falling in the bandgap, prohibiting forward propagation and leading to the isolation ratio of more than 30 dB. Resultantly, such a comoving slab exhibits an order-of-magnitude larger isolation ratio compared with the cases of fixed interfaces. Next, we show that, in superluminal modulation regime, isolation can be realized based on a completely new mechanism originating from temporal amplification inside the momentum bandgap. Such a modulation opens asymmetric momentum bandgaps, in which Bloch-Floquet modes display exponential amplification. Hence, forward propagating mode experiences significant temporal amplification, while backward one attenuates due to inherent plasmonic loss, resulting in high isolation ratio of around 30 dB. The presented results pave the way towards magnetless optical isolation or circulation with high performances by using space-time modulated systems.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"587 ","pages":"Article 131957"},"PeriodicalIF":2.2,"publicationDate":"2025-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143916478","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":"Directional torsion sensor based on aluminum-coated tapered capillary hollow core fiber","authors":"Cipriano Guzmán-Cano ,&nbsp;Laura Giselle Martinez-Ramirez ,&nbsp;Iván Hernández-Romano ,&nbsp;Marco Bianchetti ,&nbsp;Vladimir P. Minkovich ,&nbsp;Natanael Cuando-Espitia ,&nbsp;Juan Manuel Sierra-Hernandez ,&nbsp;Sigifredo Marrujo-García","doi":"10.1016/j.optcom.2025.131954","DOIUrl":"10.1016/j.optcom.2025.131954","url":null,"abstract":"<div><div>Based on capillary hollow core fiber (CHCF) that has a tapered section, a Mach-Zehnder interferometer is constructed to measure torsion, and it is capable of discriminating torsion direction using a signal processing method. A novel technique of splicing and tapering CHCF is developed to construct this sensor, using a standard splicer, where a section of SMF is spliced to 1 mm of MMF and then to 1.5 mm of CHCF; the process is repeated to have two identical fiber structures. This original program splices these fiber structures (both sections of CHCF) and then tapers to a waist of 30 μm. During this process, the central hollow does not exhibit deformation or collapse. For clockwise (CW), the torsion sensitivity is 0.674 ± 0.009 dB/(rad/m) in the range from 0.727 to 5.091 rad/m; for counterclockwise (CCW), the torsion sensitivity is −0.918 ± 0.012 dB/(rad/m) in the range from −4.363 to −0.727 rad/m. The performance of the sensor is upgraded by depositing two diametrically opposed aluminum films (30 nm). For CW, the torsion sensitivity is 4.270 ± 0.093 dB/(rad/m) in the range from 0 to 2.909 rad/m; for CCW, the torsion sensitivity is −4.762 ± 0.107 dB/(rad/m) in the range from −2.909 to 0 rad/m. Applying the Fast Fourier transform (FFT) to the transmission spectra of the coated sensor is feasible to distinguish the torsion direction. The proposed fiber structure used standard equipment for its construction, low-cost fiber, and simple fabrication, and it is efficient in identifying the twist direction. All these qualities make the sensor adequate for structural monitoring.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"587 ","pages":"Article 131954"},"PeriodicalIF":2.2,"publicationDate":"2025-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143916480","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":"Light coupling to waveguides via angularly tuned photonic nanojet","authors":"P.K. Kushwaha ,&nbsp;K.Y. Singh ,&nbsp;H.S. Mahor ,&nbsp;P.K. Singh","doi":"10.1016/j.optcom.2025.131938","DOIUrl":"10.1016/j.optcom.2025.131938","url":null,"abstract":"<div><div>We conduct a theoretical and experimental study on the generation and control of angularly tuned photonic nanojets (PNJs) using a dielectric microsphere under off-axis Gaussian beam excitation for efficient waveguide coupling. Our results show that under plane wave excitation, the nanojet's photon flux in the shadow region remains aligned with the incident beam, regardless of its angle. However, employing a focused Gaussian beam with off-axis excitation enables precise steering of the nanojet emission by up to 80° relative to the illumination axis. Furthermore, we experimentally demonstrate the application of this technique for coupling light into a waveguide, validating its feasibility for integrated photonic systems. The ability to manipulate PNJ direction through off-axis excitation offers enhanced control over optical signal routing. This method extends across a broad wavelength range, making it suitable for various photonic and plasmonic applications, including optical interconnects, waveguide-based sensing, and signal processing.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"587 ","pages":"Article 131938"},"PeriodicalIF":2.2,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143923532","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}