Optics Communications最新文献

{"title":"Impact of non-radiative recombination and optical feedback strength on field fluctuations, noise, and spectral line shape in laser diodes","authors":"Jabir Hakami ,&nbsp;Abu Mohamed Alhasan ,&nbsp;A.Y. Madkhli ,&nbsp;Salah Abdulrhmann","doi":"10.1016/j.optcom.2026.132883","DOIUrl":"10.1016/j.optcom.2026.132883","url":null,"abstract":"<div><div>In this article, we present findings on the impacts of external optical feedback (OFB), non-radiative recombination (NRR), and injection current on the lasing field fluctuations and the spectral characteristics of laser diodes (LDs). Utilizing an advanced simulation model, we explore OFB as a series of round trip time delays in the external-cavity. Our research categorizes laser dynamics through bifurcation diagrams of photon numbers and analyzes noise characteristics across three operational regions: continuous-wave (CW) operation under weak OFB, chaotic behavior under moderate OFB, and stable CW operation under strong OFB. Notably, lower NRR stabilize laser output, facilitating periodic oscillation (PO) or CW modes essential for high performance. Reducing the NRR in solitary lasers narrows the line shape, enhancing optical performance. In CW operation under strong OFB conditions, low-frequency components of relative intensity noise (RIN) and frequency noise (FN) are substantially suppressed. However, noise levels increase during coherence collapse and at higher NRR. Our findings indicate that while moderate OFB can induce coherence collapse leading to broadened spectral peaks, very strong OFB enhances coherence, yielding sharp central peaks and allowing for CW or PO. Overall, our research highlights the critical role of a low NRR in enhancing the stability of laser diodes while revealing that a higher NRR can improve coherence in specific contexts. These insights pave the way for future advancements in laser technology, particularly for applications requiring precision and reliability.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"606 ","pages":"Article 132883"},"PeriodicalIF":2.5,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145980883","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":"Quasi-bound state in continuum assisted lasing in one-dimensional blazed grating","authors":"Diksha Sharma ,&nbsp;Jyoti Mandal ,&nbsp;Anjani Kumar Tiwari","doi":"10.1016/j.optcom.2026.132877","DOIUrl":"10.1016/j.optcom.2026.132877","url":null,"abstract":"<div><div>Quasi-bound states in the continuum (QBIC) modes exhibit ultra-high quality factors with minimal radiative losses, enabling enhanced light–matter interactions and sharper spectral features. Realizing QBIC modes in practical devices typically requires carefully engineered structural asymmetry and precise geometric tuning, which pose significant fabrication challenges. In contrast, the blazed grating inherently introduces the required asymmetry and is easier to fabricate, making it a promising platform for realizing QBIC modes. In this paper, we numerically investigate the QBIC modes of a one-dimensional blazed grating structure on a silica platform. The optimized blazed grating supports both accidental and symmetry-protected QBIC modes for transverse electric and transverse magnetic polarization in the visible spectrum. The accidental QBIC modes are identified by their symmetric field profile, and the multipolar analysis confirms the dominant contribution from the toroidal dipole moment in the blazed grating structure. The symmetry-protected QBIC modes are identified through the antisymmetric field profile. At normal incidence under transverse electric polarization, the quality factors of the accidental and symmetry-protected QBIC modes are <span><math><mrow><mn>1</mn><mo>.</mo><mn>6</mn><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>4</mn></mrow></msup></mrow></math></span> and <span><math><mrow><mn>2</mn><mo>.</mo><mn>9</mn><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>4</mn></mrow></msup></mrow></math></span>, respectively. For transverse magnetic polarization, the quality factors of accidental and symmetry-protected QBIC modes are <span><math><mrow><mn>5</mn><mo>.</mo><mn>9</mn><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>4</mn></mrow></msup></mrow></math></span> and <span><math><mrow><mn>7</mn><mo>.</mo><mn>2</mn><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>4</mn></mrow></msup></mrow></math></span>. QBIC-assisted lasing is realized by incorporating optical gain in the ambient medium. Furthermore, by varying the angle of incidence, we show that the spectral position of the QBIC lasing mode can be tuned, enabling the realization of a QBIC-based tunable laser operating in the visible spectrum.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"606 ","pages":"Article 132877"},"PeriodicalIF":2.5,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145981670","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":"Scalable architectures for quantum key distribution in real world networks","authors":"Ankit Kumar ,&nbsp;Abdul Khader Jilani Saudagar ,&nbsp;Abhishek Kumar","doi":"10.1016/j.optcom.2026.132911","DOIUrl":"10.1016/j.optcom.2026.132911","url":null,"abstract":"<div><div>Quantum Key Distribution (QKD) is emerging as a foundational technology for secure communications in the quantum era, offering information-theoretic security based on the principles of quantum mechanics. However, despite notable progress, the real-world adoption of QKD continues to encounter obstacles, such as limited scalability, high implementation costs, challenges in integration with classical and cloud-native infrastructures, and reduced performance over long distances. To address these issues, this study introduces the Scalable Modular QKD (SM-QKD) framework, an innovative architecture designed to support modularity, scalability, and hybrid quantum-classical orchestration. SM-QKD incorporates adaptive optimization and seamless cloud-native integration to overcome the limitations of traditional quantum key distribution (QKD) systems. Extensive benchmarking across urban, cloud-based, and cross-domain environments revealed significant performance gains: a 41 % increase in throughput, 47 % reduction in latency, 9 % improvement in error correction success, and 33 % greater interoperability with current digital infrastructures compared to existing commercial and research-based QKD solutions. These advancements establish SM-QKD as a robust, cost-efficient, and deployment-ready framework for achieving quantum-resilient secure communications across national, enterprise, and cross-border networks and will play vital role in future economics.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"606 ","pages":"Article 132911"},"PeriodicalIF":2.5,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146039188","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":"PGC-LFA-Atan demodulation scheme for fiber interferometric sensing system under small modulation depth","authors":"Ziyue Wang ,&nbsp;Hanfeng Xu ,&nbsp;Yanli Zhang ,&nbsp;Bing Wei ,&nbsp;Xiaofeng Jin","doi":"10.1016/j.optcom.2026.132879","DOIUrl":"10.1016/j.optcom.2026.132879","url":null,"abstract":"<div><div>An improved phase-generated carrier linear-fitting algorithm arctangent (PGC-LFA-Atan) method for signal demodulation of fiber interferometric sensors under small modulation depth is proposed and demonstrated. By utilizing the random sample consensus algorithm in the linear fitting process and subsequently using a nonlinear fitting curve, the distortion in the demodulated signal caused by modulation depth variation and carrier phase delay under a small modulation depth is greatly suppressed. Experimental results show that the total harmonic distortion of the demodulated signal is lower than 0.4 % and the signal-to-noise and distortion ratio is higher than 48 dB in the modulation range between 0.1 and 0.5 rad. The demodulated phase resolution is 1.78 × 10⁻⁵ rad/Hz^1/2 @ 100 Hz and the dynamic range reaches 117.12 dB @ 100 Hz when the modulation depth is as low as 0.1 rad.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"605 ","pages":"Article 132879"},"PeriodicalIF":2.5,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145929149","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":"Simultaneous refractive index and thickness measurement based on dual-wavelength digital holography","authors":"Hanwei Cheng ,&nbsp;Wenjian Wang ,&nbsp;Yihua Dong ,&nbsp;Rui Yan ,&nbsp;Nauman Ali ,&nbsp;Sha An ,&nbsp;Juanjuan Zheng ,&nbsp;Peng Gao ,&nbsp;Xiaofang Wang ,&nbsp;Tanping Li ,&nbsp;Kai Wen ,&nbsp;Peng Gao","doi":"10.1016/j.optcom.2025.132858","DOIUrl":"10.1016/j.optcom.2025.132858","url":null,"abstract":"<div><div>In this work, we propose a novel method for simultaneously measuring the thickness and refractive index (RI) of transparent samples based on dual-wavelength on-axis digital holography. A sample under test is rotated from 0° to 20° with an interval of 1°, and three-step phase-shifting holograms are recorded for each rotation angle. For each wavelength, a phase-versus-angle response curve is constructed from a series of hologram rotations, then fitted with a physical model to determine the thickness and RI of the sample. This method features a high RI and thickness measurement precision of ∼5 × 10⁻⁵ and 1 × 10⁻², and a high stability of 3.7 × 10⁻⁵ over a period of 5 min. Combining dual-wavelength data and the Cauchy dispersion formula, RI at any wavelength within the visible spectral range can be predicted. We can envisage that the proposed technique will find widespread application in related industries, such as morphology measurement.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"605 ","pages":"Article 132858"},"PeriodicalIF":2.5,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145929150","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":"Theoretical investigation on a flexible broadband metamaterial absorber in long-wave infrared band","authors":"Longteng Qu ,&nbsp;Ming Zhang ,&nbsp;Tian Wang ,&nbsp;Zhuoran Xu ,&nbsp;Jian Wu ,&nbsp;Ruzhi Wang","doi":"10.1016/j.optcom.2026.132878","DOIUrl":"10.1016/j.optcom.2026.132878","url":null,"abstract":"<div><div>A flexible metamaterial absorber with a metal-dielectric-metal configuration is proposed for operation in the long-wave infrared (LWIR) region. The structure consists of a patterned Cr resonator array, an intermediate Ge/PDMS composite dielectric spacer, and a Ti substrate. Numerical simulations demonstrate that the absorber achieves an average absorption of 96.01 % across 8.01–13.96 μm, perfectly matching the full LWIR region and highlighting its strong application potential within the infrared atmospheric window (8–14 μm). The proposed absorber also exhibits excellent polarization independence and maintains high performance under large-angle incidence, ensuring robustness in complex natural environments. Systematic analyses of its structural parameters and applicability to alternative refractory materials verify the distinct advantage of the proposed absorber in achieving broadband absorption. The underlying absorption mechanism is clarified via electromagnetic field analysis at distinct resonance peaks, revealing that the broadband absorption arises from the synergistic coupling of multiple resonance modes. Collectively, these characteristics highlight the great potential of the proposed absorber for practical applications in LWIR remote sensing, environmental monitoring, and night vision imaging.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"605 ","pages":"Article 132878"},"PeriodicalIF":2.5,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145929151","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":"Fiber optic accelerometer with high quality factor and sensitivity enabled by lateral force","authors":"Lingjing Ran,&nbsp;Yueqi Zhang,&nbsp;Ranyang Li,&nbsp;Shuangshuang Li,&nbsp;Rui Zhou,&nbsp;Xueguang Qiao","doi":"10.1016/j.optcom.2025.132818","DOIUrl":"10.1016/j.optcom.2025.132818","url":null,"abstract":"<div><div>We propose and demonstrate a structural accelerometer based on a fiber Bragg grating Fabry–Perot interferometer that abandons the traditional mechanical structure. External perturbations act directly upon the wound fiber. By tuning the initial winding tension, the clamping component width, and the fiber suspension distance, both the sensitivity and natural frequency of the accelerometer can be adjusted. We derive the theoretical formulations, and the experimental results exhibit close agreement with the simulations. The theoretical expressions for the accelerometer’s sensitivity and natural frequency are confirmed through experiments. The experiment results indicate that adjusting relevant parameters can tune the accelerometer’s natural frequency between 30 and 110 Hz, with a maximum sensitivity reaching 1556.76 rad/g at 30 Hz. Increasing the fiber winding tension effectively reduces sensitivity, thereby expanding the accelerometer’s working bandwidth. The size and sensitivity of the accelerometer can be balanced by adjusting the clamping component width and the suspension distance. This study offers general design guidelines for the development of analogous sensors in the field of fiber optic sensing.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"604 ","pages":"Article 132818"},"PeriodicalIF":2.5,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145939644","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":"Profile dispersion characteristics of graded-index multimode fiber and its impact on bandwidth","authors":"Qinglong Zhang,&nbsp;Yi Zhan,&nbsp;Yihan Wang,&nbsp;An Wang","doi":"10.1016/j.optcom.2025.132815","DOIUrl":"10.1016/j.optcom.2025.132815","url":null,"abstract":"<div><div>The bandwidth of multimode fiber (MMF) can be limited by dispersion. Among them, the profile dispersion, though small, should not be neglected, especially in MMF with high numerical apertures, and must also be taken into account. However, profile dispersion is often neglected or only the profile dispersion parameter are discussed in conventional studies. In order to study the profile dispersion in MMF and its effect on the bandwidth, we find and validate a relatively accurate mathematical model to represent the profile dispersion of single-core graded-index MMF. The mode of MMF is solved and the profile dispersion is calculated based on MATLAB using the half-vector finite-difference method without approximating the relative refractive index difference. Through the analysis of the relationship between profile dispersion and bandwidth and mode, the results indicate that small local changes in the profile dispersion lead to abrupt changes in the bandwidth, and higher-order modes cause larger absolute value of profile dispersion, indicating that the profile dispersion has a modulating effect on the bandwidth. These findings demonstrate the potential to tailor MMF performance by selecting specific transmission modes, providing a framework to optimize fiber design to improve the performance of optical communication systems.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"605 ","pages":"Article 132815"},"PeriodicalIF":2.5,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145898017","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":"Coupling performance of a planar lens to ultra slow-light photonic crystal waveguides: Simulation-based analysis and field distribution study","authors":"M. Amraie ,&nbsp;T. Fathollahi-Khalkhali ,&nbsp;A. Aghamohammadi ,&nbsp;E. Lotfi","doi":"10.1016/j.optcom.2026.132874","DOIUrl":"10.1016/j.optcom.2026.132874","url":null,"abstract":"<div><div>This study numerically investigates methods to improve the coupling efficiency between planar photonic crystal (PC) lenses and ultra-slow light PC waveguides. The structures consist of aluminum oxide rod arrays in air, where modified and geometrically optimized W1 and W2 waveguides are combined with a linearly graded square lattice PC lens to achieve efficient coupling. A single frequency source excites various configurations of slow light waveguides, enabling a controlled evaluation of their coupling behavior. The results show that the optimized designs preserve high coupling efficiency <span><math><mrow><mn>11.75</mn><mspace></mspace><mi>d</mi><mi>B</mi></mrow></math></span>, with the best configuration exhibiting a marked enhancement when even compared to standard photonic crystal waveguides. These findings demonstrate that properly engineered planar PC lenses can reliably inject light into ultra-slow light PC waveguides with minimal loss, supporting the development of compact photonic integrated circuits that require enhanced light–matter interactions and precise control of signal delay.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"605 ","pages":"Article 132874"},"PeriodicalIF":2.5,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145980303","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":"Large-area holographic display by depth-multiplexed spatial region repositioning on a single spatial light modulator","authors":"Jianglian Wang,&nbsp;Atsushi Okamoto","doi":"10.1016/j.optcom.2025.132852","DOIUrl":"10.1016/j.optcom.2025.132852","url":null,"abstract":"<div><div>We propose a depth-multiplexed holographic display based on spatial region repositioning that expands the effective display area under the intrinsic space–bandwidth product (SBP) limitation of a single spatial light modulator (SLM). Unlike conventional multi-plane holographic displays, which reconstruct different content at distinct axial depths, our approach partitions a large target image into distinct spatial regions, with each region corresponding to a specific axial depth. A compact beam-splitter assembly then optically repositions these depth-multiplexed regions onto the same observation plane, yielding a single enlarged display while still employing a single SLM. The results of numerical simulations and optical experiments verify that the proposed method significantly enlarges the area for both two- and three-dimensional holographic displays. In contrast to conventional approaches that expand the area by increasing the physical modulation aperture or by integrating multiple synchronized SLMs and customized diffractive elements, the proposed method offers a compact and practical solution for large-area holographic displays.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"604 ","pages":"Article 132852"},"PeriodicalIF":2.5,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145886065","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}